PlainTariff

HTS Chapter 91 · Section XVIII

Clocks and watches and parts thereof

Chapter 91 averages a 4.6% general (MFN) duty across its 174 rated tariff lines, with the steepest line reaching 14%.

4.6%
avg MFN duty
14%
highest line
174
rated tariff lines
11%
enter duty-free

Tariff lines in Chapter 91 by duty-rate band

How the 174 rated lines in this chapter distribute across general (MFN) rate ranges

Duty-free190.1–5%915–10%5410–20%3

Source: USITC HTS 2026 As of 2026

About HTS Chapter 91

HTS Chapter 91 - Clocks and watches and parts thereof - organizes 314 tariff classifications in the US Harmonized Tariff Schedule. Of these, 174 carry explicit duty rates at the tariff-line level, meaning importers can look up a specific Column 1 General (MFN) rate for every qualifying shipment. Chapter 91 sits within Section XVIII (Optical, Photographic, Measuring, Medical Instruments), which groups commercially related product categories together.

The average general duty rate across all tariff lines in this chapter is 4.6%, with the highest individual rate reaching 14%. Duty burden varies widely across tariff lines within this chapter, classification precision matters. Below, each line links to its individual detail page showing General, Special (FTA), and Column 2 rates.

Use this chapter page as the entry point for classifying any product that falls under clocks and watches and parts thereof. The tree below preserves the HTS indentation hierarchy (heading → subheading → tariff line), so you can narrow from broad category to specific 8-10 digit code. All data comes from the US International Trade Commission (USITC) HTS 2026 Basic Edition, the official schedule of import duties used by US Customs and Border Protection.

Chapter 91 At a Glance

Tariff distribution statistics for HTS Chapter 91 from USITC 2026 Basic Edition.
Metric Value Notes
Total tariff classifications 314 All headings, subheadings, and tariff lines.
Lines with explicit rates 174 Tariff lines carrying a Column 1 General duty.
Average general rate 4.6% Mean MFN rate across rated lines.
Highest line rate 14% Peak Column 1 General rate within the chapter.

Source: USITC Harmonized Tariff Schedule 2026 Basic Edition. Computed at last data refresh, see methodology.

Tariff Lines

9101 Wrist watches, pocket watches and other watches, including stop watches, with case of precious metal or of metal clad with precious metal:
Wrist watches, electrically operated, whether or not incorporating a stop watch facility:
9101.11 With mechanical display only:
9101.11.40 Having no jewels or only one jewel in the movement
51¢ each + 6.25% on the case and strap, band or bracelet + 5.3% on the battery
87¢ each + 6.25% on the case and strap, band or bracelet + 5.3% on the battery
9101.19 Other:
9101.19.20 With opto-electronic display only.
Free
Straps, bands or bracelets entered with watches of subheading 9101.19.20 and classifiable therewith pursuant to additional U.S. note 2 to this chapter; all the foregoing whether or not attached to such watches at the time of entry:
9101.19.20.20 Of textile material or of base metal, whether or not gold- or silver-plated
No.
9101.19.20.40 Other
No.
9101.19.20.80 Other
No.
9101.19.40 Other, having no jewels or only one jewel in the movement
41¢ each + 5% on case and strap, band or bracelet + 4.2% on the battery
61¢ each + 4.4% on case and strap, band or bracelet + 3.7% on the battery
Other wrist watches, whether or not incorporating a stop watch facility:
9101.21 With automatic winding:
Having over 17 jewels in the movement:
Straps, bands or bracelets entered with watches of subheading 9101.21.50 and classifiable therewith pursuant to additional U.S. note 2 to this chapter; all the foregoing whether or not attached to such watches at the time of entry:
9101.21.10.00 Of textile material or of base metal, whether or not gold- or silver-plated
No.
3.1%
No.
3.1%
Free
$1.61 each + 4.4% on the case and strap, band or bracelet
9101.29 Other:
9101.29.10 Having no jewels or only one jewel in the movement
40¢ each + 5% on the case and strap, band or bracelet
9101.29.20 Having over 1 jewel but not over 7 jewels in the movement
61¢ each + 4.4% on the case and strap, band or bracelet
Having over 7 jewels but not over 17 jewels in the movement:
With movement valued not over $15 each
9101.29.30 With movement measuring not over 15.2 mm
$2.28 each + 5% on the case and strap, band or bracelet
9101.29.40 With movement measuring over 15.2 mm
$1.92 each + 5% on the case and strap, band or bracelet
9101.29.50 With movement valued over $15 each
90¢ each + 4.4% on the case and strap, band or bracelet
Having over 17 jewels in the movement:
Straps, bands or bracelets entered with watches of subheading 9101.29.90 and classifiable therewith pursuant to additional U.S. note 2 to this chapter; all the foregoing whether or not attached to such watches at the time of entry:
9101.29.70.00 Of textile material or of base metal, whether or not gold- or silver-plated
No.
3.1%
No.
3.1%
Free
Other:
9101.91 Electrically operated:
9101.91.20.00 With opto-electronic display only
No.
Free
Other:
9101.91.40 Having no jewels or only one jewel in the movement
Free
Free
9101.99 Other:
9101.99.20 Having no jewels or not over 7 jewels in the movement
Free
Having over 7 but not over 17 jewels in the movement:
9101.99.40 With movement valued not over $15 each
98¢ each + 3% on the case
9101.99.60 With movement valued over $15 each
Free
9101.99.80 Having over 17 jewels in the movement
Free
9102 Wrist watches, pocket watches and other watches, including stop watches, other than those of heading 9101:
Wrist watches, electrically operated, whether or not incorporating a stop watch facility:
9102.11 With mechanical display only:
Having no jewels or only one jewel in the movement:
With strap, band or bracelet of textile material or of base metal, whether or not gold- or silver-plated
9102.11.10 With gold- or silver-plated case
44¢ each + 6% on the case + 14% on the strap, band or bracelet + 5.3% on the battery
40¢ each + 8.5% on the case + 14% on the strap, band or bracelet + 5.3% on the battery
Other:
9102.11.30 With gold- or silver-plated case
44¢ each + 6% on the case + 2.8% on the strap, band or bracelet + 5.3% on the battery
40¢ each + 8.5% on the case + 2.8% on the strap, band or bracelet + 5.3% on the battery
Other:
With strap, band or bracelet of textile material or of base metal, whether or not gold- or silver-plated
9102.11.50 With gold- or silver-plated case
80¢ each + 6% on the case + 14% on the strap, band or bracelet + 5.3% on the battery
76¢ each + 8.5% on the case + 14% on the strap, band or bracelet + 5.3% on the battery
Other:
9102.11.70 With gold- or silver-plated case
80¢ each + 6% on the case + 2.8% on the strap, band or bracelet + 5.3% on the battery
76¢ each + 8.5% on the case + 2.8% on the strap, band or bracelet + 5.3% on the battery
9102.12 With opto-electronic display only:
Straps, bands or bracelets entered with watches of subheading 9102.12.80 and classifiable therewith pursuant to additional U.S. note 2 to this chapter; all the foregoing whether or not attached to such watches at the time of entry:
9102.12.20.00 Of textile material or of base metal, whether or not gold- or silver-plated
No.
Free
No.
Free
No.
Free
9102.19 Other:
Having no jewels or only one jewel in the movement:
9102.19.20 With strap, band or bracelet of textile material or of base metal, whether or not gold-or silver-plated
32¢ each + 4.8% on the case + 11% on the strap, band or bracelet + 4.2% on the battery
32¢ each + 4.8% on the case + 2.2% on the strap, band or bracelet + 4.2% on the battery
Other:
9102.19.60 With strap, band or bracelet of textile material or of base metal, whether or not gold-or silver-plated
57¢ each + 4.5% on the case + 10.6% on the strap, band or bracelet + 4% on the battery
57¢ each + 4.5% on the case + 2.1% on the strap, band or bracelet + 4% on the battery
Other wrist watches, whether or not incorporating a stop watch facility:
9102.21 With automatic winding:
Having no jewels or only one jewel in the movement:
9102.21.10 With strap, band or bracelet of textile material or of base metal, whether or not gold- or silver-plated
75¢ each + 6% on the case + 14% on the strap, band or bracelet
75¢ each + 6% on the case + 2.8% on the strap, band or bracelet
Having over one jewel but not over 17 jewels in the movement:
9102.21.30 With strap, band or bracelet of textile material or of base metal, whether or not gold- or silver-plated
$1.75 each + 4.8% on the case + 11.2% on the strap, band or bracelet
$1.75 each + 4.8% on the case + 2.2% on the strap, band or bracelet
Having over 17 jewels in the movement:
9102.21.70 With strap, band or bracelet of textile material or of base metal, whether or not gold- or silver-plated
$1.53 each + 4.2% on the case + 9.8% on the strap, band or bracelet
$1.53 each + 4.2% on the case + 2% on the strap, band or bracelet
9102.29 Other:
Having no jewels or only one jewel in the movement:
With strap, band or bracelet of textile material or of base metal, whether or not gold- or silver-plated:
9102.29.02.00 Straps, bands or bracelets entered with watches of subheading 9102.29.04 and classifiable therewith pursuant to additional U.S. note 2 to this chapter; all the foregoing whether or not attached to such watches at the time of entry
No.
14%
40¢ each + 6% on the case
40¢ each + 6% on the case + 2.8% on the strap, band or bracelet
Having over one jewel but not over 7 jewels in the movement:
9102.29.15 With strap, band or bracelet of textile material or of base metal, whether or not gold- or silver-plated
58¢ each + 4.6% on the case + 10.6% on the strap, band or bracelet
56¢ each + 4.4% on the case + 2% on the strap, band or bracelet
Having over 7 but not over 17 jewels in the movement:
With movement valued not over $15 each:
With movement measuring not over 15.2 mm:
9102.29.25 With strap, band or bracelet of textile material or of base metal, whether or not gold- or silver- plated
$2.19 each + 4.8% on the case + 11.2% on the strap, band or bracelet
$2.19 each + 4.8% on the case + 2.2% on the strap, band or bracelet
With movement measuring over 15.2 mm:
9102.29.35 With strap, band or bracelet of textile material or of base metal, whether or not gold- or silver- plated
$1.61 each + 4.2% on the case + 9.8% on the strap, band or bracelet
$1.83 each + 4.8% on the case + 2.2% on the strap, band or bracelet
With movement valued over $15 each:
9102.29.45 With strap, band or bracelet of textile material or of base metal, whether or not gold- or silver-plated
93¢ each + 4.8% on the case + 11.2% on the strap, band or bracelet
93¢ each + 4.8% on the case + 2.2% on the strap, band or bracelet
Having over 17 jewels in the movement:
9102.29.55 With strap, band or bracelet of textile material or of base metal, whether or not gold-or silver-plated
$1.55 each + 4.2% on the case + 9.9% on the strap, band or bracelet
$1.75 each + 4.8% on the case + 2.2% on the strap, band or bracelet
Other:
9102.91 Electrically operated:
9102.91.20 With opto-electronic display only
3.9% on the movement and case + 5.3% on the battery
Other:
9102.91.40 Having no jewels or only one jewel in the movement
40¢ each + 6% on the case + 5.3% on the battery
76¢ each + 6% on the case + 5.3% on the battery
9102.99 Other:
9102.99.20 Having no jewels or not over 7 jewels in the movement
20¢ each + 3% on the case
Having over 7 but not over 17 jewels in the movement:
9102.99.40 With movement valued not over $15 each
92¢ each + 3% on the case
9102.99.60 With movement valued over $15 each
$1.16 each + 6% on the case
9102.99.80 Having over 17 jewels in the movement
$2.19 each + 6% on the case
9103 Clocks with watch movements, excluding clocks of heading 9104:
9103.10 Electrically operated:
9103.10.20 With opto-electronic display only
2.6% on the movement and case + 3.6% on the battery
Other:
9103.10.40 Having no jewels or only one jewel in the movement
24¢ each + 4.5% on the case + 3.5% on the battery
48¢ each + 4.6% on the case + 3.5% on the battery
24¢ each + 4.6% on the case
9104.00 Instrument panel clocks and clocks of a similar type for vehicles, aircraft, spacecraft or vessels:
With clock movements measuring over 50 mm in width or diameter:
Valued not over $10 each:
9104.00.05 With opto-electronic display only
2.6% on the movement and case + 3.5% on the battery
Other:
9104.00.10 Electric (including battery operated)
20¢ each + 4.3% on the movement and case + 3.5% on the battery
No.
30¢ each + 6.4%
Valued over $10 each:
9104.00.25 With opto-electronic display only
3.9% on the movement and case + 5.3% on the battery
Other:
9104.00.30 Electric (including battery operated)
30¢ each + 4.3% on the movement and case + 3.5% on the battery
No.
30¢ each + 4.3%
Other:
9104.00.45 With opto-electronic display only
2.6% on the movement and case + 3.5% on the battery
Other:
9104.00.50 Electric (including battery operated)
20¢ each + 4.6% on the case + 3.5% on the battery
19¢ each + 4.5% on the case
9105 Other clocks:
Alarm clocks:
9105.11 Electrically operated:
9105.11.40 With opto-electronic display only
3.9% on the movement and case + 5.3% on the battery
30¢ each + 6.9% on the case + 5.3% on the battery
9105.19 Other:
With movement measuring not over 50 mm in width or diameter:
9105.19.10 Not constructed or designed to operate for over 47 hours without rewinding
30¢ each + 6.9% on the case
Constructed or designed to operate for over 47 hours without rewinding:
9105.19.20 Having no jewels or only one jewel
60¢ each + 6.9% on the case
9105.19.30 Having over one jewel
43¢ each + 2.8¢/jewel over 7 + 3.7% on the case
Other:
9105.19.40.00 Valued not over $5 each
No.
15¢ each + 6.4%
9105.19.50.00 Valued over $5 each
No.
23¢ each + 3.2%
Wall clocks:
9105.21 Electrically operated:
9105.21.40 With opto-electronic display only
3.9% on the movement and case+ 5.3% on the battery
30¢ each + 6.9% on the case + 5.3% on the battery
9105.29 Other:
With movement measuring not over 50 mm in width or diameter:
9105.29.10 Not constructed or designed to operate for over 47 hours without rewinding
20¢ each + 4.6% on the case
Constructed or designed to operate for over 47 hours without rewinding:
9105.29.20 Having no jewels or only one jewel
40¢ each + 4.6% on the case
9105.29.30 Having over one jewel
57¢ each + 3.7¢/jewel over 7 + 4.9% on the case
Other:
9105.29.40.00 Valued not over $5 each
No.
15¢ each + 6.4%
9105.29.50.00 Valued over $5 each
No.
30¢ each + 4.3%
Other:
9105.91 Electrically operated:
9105.91.40 With opto-electronic display only
3.9% on the movement and case+ 5.3% on the battery
30¢ each + 6.9% on the case + 5.3% on the battery
9105.99 Other:
9105.99.10.00 Standard marine chronometers having spring-detent escapements
No., Jwls.
17¢ each + 2.5% + 1¢/jewel
Other, with movement measuring not over 50 mm in width or diameter:
9105.99.20 Not constructed or designed to operate for over 47 hours without rewinding
Free
Constructed or designed to operate for over 47 hours without rewinding:
9105.99.30 Having no jewels or only one jewel
Free
9105.99.40 Having over one jewel
Free
Other:
9105.99.50.00 Valued not over $5 each
No.
7.5¢ each + 3.2%
9105.99.60.00 Valued over $5 each
No.
23¢ each + 3.2%
9106 Time of day recording apparatus and apparatus for measuring, recording or otherwise indicating intervals of time, with clock or watch movement or with synchronous motor (for example, time registers, time-recorders):
9106.10.00.00 Time registers; time-recorders
No., Jwls.
36¢ each + 5.6% + 2¢/jewel
9106.90 Other:
9106.90.20.00 Parking meters
No., Jwls.
36¢ each + 5.6% + 2¢/jewel
9106.90.40.00 Time locks valued over $10 each
No., Jwls.
36¢ each + 5.6% + 2¢/jewel
Other:
Apparatus for measuring, recording, or otherwise indicating intervals of time, with clock or watch movements, battery powered:
9106.90.55 With opto-electronic display only
3.9% on the apparatus + 5.3% on the battery
No., Jwls.
15¢ each + 2.3% + 0.8¢/jewel
Other:
9106.90.75.00 Apparatus for measuring, recording or otherwise indicating intervals of time, with clock or watch movements, AC powered and with opto-electronic display only
No.
3.9%
No., Jwls.
15¢ each + 2.3% + 0.8¢/jewel
9107.00 Time switches with clock or watch movement or with synchronous motor:
9107.00.40 Valued not over $5 each
15¢ each + 4% + 2.5¢/jewel
9107.00.40.40 Time switches that operate on a fixed-time cycle, of a type used in household type refrigerators and combined refrigerator-freezers, to alternately control the operations of the compressor and the defrost unit (defrost timers)
No., Jwls.
9107.00.40.80 Other
No., Jwls.
9107.00.80.00 Valued over $5 each
No., Jwls.
45¢ each + 6.4% + 2.5¢/jewel
9108 Watch movements, complete and assembled:
Electrically operated:
9108.11 With mechanical display only or with a device to which a mechanical display can be incorporated:
9108.11.40 Having no jewels or only one jewel
36¢ each + 5.3% on the battery
72¢ each + 5.3% on the battery
9108.12.00 With opto-electronic display only
3.1% on the movement + 4.2% on the battery
9108.19 Other:
9108.19.40 Having no jewels or only one jewel
28¢ each + 4.2% on the battery
53¢ each + 3.9% on the battery
9108.20 With automatic winding:
9108.20.40.00 Having over 17 jewels
No.
Free
No.
Free
9108.90 Other:
Having no jewels or only one jewel:
9108.90.10.00 Measuring 33.8 mm or less
No.
29¢ each
No.
25¢ each
Having over one jewel but not over 7 jewels:
9108.90.30.00 Measuring 33.8 mm or less
No.
57¢ each
No.
25¢ each
Having over 7 jewels but not over 17 jewels:
Measuring 33.8 mm or less
Valued not over $15 each
9108.90.50.00 Measuring not over 15.2 mm
No.
$2.16 each
9108.90.60.00 Measuring over 15.2 mm
No.
$1.80 each
9108.90.70.00 Valued over $15 each
No.
90¢ each
Other:
9108.90.80.00 Valued not over $15 each
No.
$1.44 each
9108.90.85.00 Valued over $15 each
No.
Free
Having over 17 jewels:
9108.90.90.00 Measuring 33.8 mm or less
No.
$1.50 each
No.
$1.72 each
9109 Clock movements, complete and assembled:
9109.10 Electrically operated:
Of alarm clocks:
9109.10.10 With opto-electronic display only
3.9% on the movement + 5.3% on the battery
Other:
9109.10.20 Measuring not over 50 mm in width or diameter
30¢ each + 5.3% on the battery
Other:
9109.10.30 Valued not over $5 each
7.5¢ each + 3.2% on the movement + 2.6% on the battery
9109.10.40 Valued over $5 each
22¢ each + 3.2% on the movement + 2.6% on the battery
Other:
9109.10.50 With opto-electronic display only
3.9% on the movement + 5.3% on the battery
Other:
9109.10.60 Measuring not over 50 mm in width or diameter
20¢ each + 3.5% on the battery
Other:
9109.10.70 Valued not over $5 each
12¢ each + 5.1% on the movement + 4.2% on the battery
9109.10.80 Valued over $5 each
30¢ each + 4.3% on the movement + 3.5% on the battery
9109.90 Other:
9109.90.20.00 Measuring not over 50 mm in width or diameter
No.
20¢ each
Other:
9109.90.40.00 Valued not over $5 each
No.
15¢ each + 6.4%
9109.90.60.00 Valued over $5 each
No.
30¢ each + 4.3%
9110 Complete watch or clock movements, unassembled or partly assembled (movement sets); incomplete watch or clock movements, assembled; rough watch or clock movements:
Of watches:
9110.11.00.00 Complete movements, unassembled or partly assembled (movement sets)
No.
The rate applicable to the complete, assembled movement
9110.12.00.00 Incomplete movements, assembled
No.
9%
9110.19.00.00 Rough movements
No.
9%
9110.90 Other:
9110.90.20.00 Complete movements, unassembled or partly assembled (movement sets)
No.
The rate applicable to the complete, assembled movement
Other:
9110.90.40.00 Consisting of two or more pieces or parts fastened or joined together
No.
4.3% + 1.7¢/jewel + 0.2¢ for each other piece or part, but if consisting in part of a plate or a set of plates the total duty shall not exceed the duty for the complete movement
No.
4.2%
9111 Watch cases and parts thereof:
9111.10.00.00 Cases of precious metal or of metal clad with precious metal
No.
12¢ each + 4.8%
9111.20 Cases of base metal, whether or not gold- or silver-plated:
9111.20.20.00 Gold- or silver-plated
No.
7¢ each + 5.4%
No.
3.6¢ each + 7.6%
9111.80.00.00 Other cases
No.
3.6¢ each + 7.6%
9111.90 Parts:
9111.90.40.00 Of precious metal or of metal clad with precious metal
No.
6.4%
Other:
9111.90.50.00 Bezels, backs and centers
No.
1.6¢ each + 6.8%
No.
6.4%
9112 Clock cases and cases of a similar type for other goods of this chapter, and parts thereof:
9112.20 Cases:
9112.20.40.00 Cases of metal
No.
3.5%
9112.20.80.00 Other cases
No.
5.5%
5.5%
9113 Watch straps, watch bands and watch bracelets, and parts thereof:
9113.10.00.00 Of precious metal or of metal clad with precious metal
doz.
4.5%
9113.20 Of base metal, whether or not gold- or silver-plated:
Straps, bands and bracelets:
9113.20.20.00 Valued not over $5 per dozen
doz.
11.2%
9113.20.40.00 Valued over $5 per dozen
doz.
11.2%
Parts:
9113.20.60.00 Of watch bracelets, valued not over $12 per dozen
kg
8.8%
8.8%
9113.90 Other:
9113.90.40.00 Of textile material
doz.
7.2%
doz.
1.8%
9114 Other clock or watch parts:
9114.30 Dials:
9114.30.40.00 Not exceeding 50 mm in width
No.
0.4¢ each + 7.2%
9114.30.80.00 Exceeding 50 mm in width
No.
4.4%
9114.40 Plates and bridges:
9114.40.20.00 Watch movement bottom or pillar plates or their equivalent
No.
12¢ each
9114.40.40.00 Any plate, or set of plates, suitable for assembling thereon a clock movement
No.
10¢ each
Other:
9114.40.60.00 For watches
No.
7.3%
No.
4.2%
9114.90 Other:
No.
Free
Assemblies and subassemblies for watch or clock movements consisting of two or more pieces or parts fastened or joined inseparably together:
9114.90.15.00 For watch movements
kg
7.2%
9114.90.30.00 For clock movements
kg
6% + 2.3¢/jewel + 0.2¢ for each other piece or part, but if consisting in part of a plate or a set of plates the total duty shall not exceed the duty for the complete movement
Springs, including hairsprings:
9114.90.34.00 For watches
No.
7.3%
No.
4.2%
Other:
9114.90.40.00 For watches
kg
8.8%
4.2%

Frequently Asked Questions

What does HTS Chapter 91 cover?
HTS Chapter 91 covers Clocks and watches and parts thereof. It contains 314 individual tariff classifications, of which 174 have specified duty rates. This chapter falls under Section XVIII (Optical, Photographic, Measuring, Medical Instruments).
What is the average tariff rate for Chapter 91?
The average general (MFN) duty rate across all tariff lines in Chapter 91 is 4.6%. The highest individual rate in this chapter is 14%. Actual duty on a specific product depends on its precise HTS classification.
How do I find the correct HTS code for my product?
Browse the tariff lines listed below organized by heading and subheading. Each item with an HTS number links to its full detail page showing general, special, and Column 2 duty rates. For complex classifications, consult a licensed customs broker or contact US Customs and Border Protection (CBP).
Are there any duty-free items in Chapter 91?
Yes, many chapters contain items with a "Free" general rate, meaning no duty is assessed for imports from most-favored-nation countries. Look for items marked "Free" in the tariff lines table below. Additional preferential rates may also apply under free trade agreements.
Where does PlainTariff get its tariff data?
All tariff data comes from the U.S. International Trade Commission (USITC) Harmonized Tariff Schedule (HTS) 2026 Basic Edition, the official schedule of US import duties.

Next steps

Find the exact rate for your product within Chapter 91.

The chapter average is an orientation only, duty is set per tariff line, and Special preferential rates may apply to qualifying origins.

Sources: U.S. International Trade Commission Harmonized Tariff Schedule (2026 Basic Edition) and FAO FAOSTAT Trade: Crops and Livestock. See our methodology for how figures are computed.

Every figure on PlainTariff is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.