Chart 1. Example of an extremely well replicated U.S. Import and Export Price Index, 2012–22
Month	Calculated index	Official index
January 2012	100.00	100.00
February 2012	99.61	99.60
March 2012	102.17	102.18
April 2012	102.43	102.41
May 2012	101.74	102.18
June 2012	92.50	92.92
July 2012	111.42	111.47
August 2012	123.43	123.48
September 2012	120.35	120.40
October 2012	116.84	116.87
November 2012	115.77	115.74
December 2012	117.96	117.89
January 2013	107.81	107.87
February 2013	113.62	113.62
March 2013	111.65	111.67
April 2013	102.20	102.28
May 2013	104.85	104.83
June 2013	107.47	107.28
July 2013	103.76	103.57
August 2013	88.28	88.19
September 2013	85.44	85.35
October 2013	74.15	74.07
November 2013	72.91	72.85
December 2013	73.52	73.48
January 2014	72.74	72.65
February 2014	75.36	75.26
March 2014	80.97	80.85
April 2014	82.87	82.64
May 2014	82.50	82.18
June 2014	75.72	75.36
July 2014	69.97	69.68
August 2014	65.44	65.18
September 2014	62.72	62.57
October 2014	58.79	58.66
November 2014	64.87	64.68
December 2014	64.75	64.58
January 2015	65.53	65.28
February 2015	63.42	63.16
March 2015	64.15	63.89
April 2015	63.52	63.26
May 2015	61.44	61.24
June 2015	60.06	59.89
July 2015	68.04	67.82
August 2015	60.40	60.12
September 2015	59.12	58.83
October 2015	62.63	62.80
November 2015	62.01	62.20
December 2015	59.44	59.59
January 2016	57.74	57.47
February 2016	60.56	60.32
March 2016	57.38	57.18
April 2016	57.35	57.31
May 2016	61.49	61.47
June 2016	65.28	65.18
July 2016	59.51	59.06
August 2016	57.25	57.04
September 2016	54.74	54.56
October 2016	56.04	56.02
November 2016	56.91	56.85
December 2016	55.50	55.49
January 2017	57.92	57.94
February 2017	59.39	59.39
March 2017	60.85	60.88
April 2017	57.79	57.57
May 2017	57.94	57.71
June 2017	58.30	58.07
July 2017	58.73	58.50
August 2017	55.57	55.36
September 2017	53.29	53.11
October 2017	54.09	54.33
November 2017	54.62	54.89
December 2017	54.98	55.19
January 2018	55.89	56.32
February 2018	60.19	60.65
March 2018	62.28	62.73
April 2018	62.39	62.83
May 2018	65.21	65.67
June 2018	63.03	63.49
July 2018	57.27	57.67
August 2018	59.14	59.66
September 2018	57.88	58.40
October 2018	57.45	57.90
November 2018	58.65	59.13
December 2018	59.80	60.28
January 2019	59.35	^[1]
February 2019	61.56	61.54
March 2019	61.28	61.14
April 2019	59.59	59.46
May 2019	59.08	58.96
June 2019	67.79	67.69
July 2019	68.53	68.42
August 2019	63.87	63.79
September 2019	56.45	56.35
October 2019	60.94	60.85
November 2019	62.07	61.97
December 2019	61.57	61.47
January 2020	62.88	62.80
February 2020	62.77	62.67
March 2020	62.31	62.30
April 2020	55.57	55.52
May 2020	51.99	52.08
June 2020	54.32	54.33
July 2020	57.25	57.28
August 2020	52.95	52.94
September 2020	58.99	58.99
October 2020	63.68	63.69
November 2020	68.59	68.62
December 2020	69.87	69.91
January 2021	80.54	80.59
February 2021	88.42	88.49
March 2021	88.30	87.47
April 2021	89.68	88.82
May 2021	116.23	115.15
June 2021	109.09	107.80
July 2021	106.95	106.02
August 2021	100.61	99.74
September 2021	88.12	87.47
October 2021	89.43	88.72
November 2021	92.00	91.27
December 2021	93.86	92.63
January 2022	98.53	97.16
February 2022	102.90	101.32
March 2022	117.69	115.31
April 2022	122.53	119.68
May 2022	128.24	125.30
June 2022	119.02	117.63
July 2022	117.95	116.47
August 2022	111.35	110.25
September 2022	111.51	110.42
October 2022	113.22	112.14
November 2022	120.48	119.28
December 2022	107.97	106.75
^[1] This index was not published in January 2019 because the data source was not available due to the government shutdown. Note: An extremely well replicated index is one that has a correlation coefficient above 0.85, a root-mean-square error less than 2.0, and a mean absolute error less than 1.0 when comparing the short-term relatives of the calculated to the official index. A well-replicated index is one that has a correlation coefficient above 0.2, a root-mean-square error below 5.0, and a mean absolute error less than 2.0. All other indexes are considered not well replicated. Source: U.S. Bureau of Labor Statistics.