IEM :: Monthly Summaries

The following tables present IEM computed monthly data summaries based on daily data provided by or computed for the IEM. A download interface exists for the daily summary information. The climatology is provided by the nearest NCEI climate station () within the current 1991-2020 dataset.

To load shown data into Microsoft Excel, highlight the table information with your mouse and then copy/paste into Excel.

Precipitation Totals [inch]

Year	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
1980	M	M	M	M	0.00	0.00	0.00	0.00	0.00	0.00	0.00	M
1981	M	M	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	M
1982	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	M
1983	M	M	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
1984	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	M
1985	M	M	0.00	0.00	M	M	M	M	M	M	M	M
1986	M	M	M	M	M	M	M	M	M	M	M	M
1987	M	M	M	M	M	M	M	M	M	M	M	M
1988	M	M	M	M	M	M	M	M	M	M	M	M
1989	M	M	M	M	M	M	M	M	M	M	M	M
1990	M	M	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
1991	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
1992	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
1993	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
1994	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
1995	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
1996	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
1997	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
1998	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
1999	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
2000	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
2001	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
2002	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
2003	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
2004	M	M	M	M	M	M	M	M	M	M	M	M
2005	M	M	M	M	M	M	M	M	M	M	M	M
2006	M	M	M	M	M	M	M	M	M	M	M	M
2007	M	0.00	M	M	M	M	M	M	M	M	M	M
2008	M	M	M	M	M	M	M	M	M	M	M	M
2009	M	M	M	M	M	M	M	M	M	M	M	M
2010	M	M	M	M	M	M	M	M	M	M	M	M
2011	M	M	M	M	M	M	M	0.00	0.00	0.00	0.00	0.00
2012	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
2013	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	M	M	M
2014	M	M	M	M	M	M	M	M	M	M	M	M
2015	M	M	M	M	M	M	M	M	M	M	M	M
2016	M	M	M	M	M	0.00	0.00	M	M	M	M	M
2017	M	M	M	M	M	M	M	M	M	M	M	M
2018	M	M	M	M	M	M	M	M	M	M	M	M
2019	M	M	M	M	M	M	M	M	M	M	M	M
2020	M	M	M	M	M	M	M	M	M	M	M	M
2021	M	M	M	M	M	M	M	M	M	M	M	M
2022	M	M	M	M	M	M	M	M	M	M	M	M
2023	M	M	M	M	M	M	M	M	M	M	M	M
2024	M	M	M	M	M	M	M	M	M	M	M	M

Average Wind Speed [MPH]

Year	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
1980	M	M	M	M	16.9	18.2	15.3	12.5	15.3	15.7	15.0	M
1981	M	M	15.8	13.1	16.2	15.4	10.9	11.7	9.5	15.3	10.9	M
1982	14.1	15.4	17.1	19.2	18.5	17.6	14.8	15.8	13.3	16.7	17.7	M
1983	M	M	21.4	19.8	16.8	17.5	15.7	15.3	15.5	15.8	16.5	14.4
1984	14.3	18.8	18.6	21.2	18.5	19.3	13.8	14.3	13.1	15.2	8.3	M
1985	M	M	23.4	20.2	M	M	M	M	M	M	M	M
1986	M	M	M	M	M	M	M	M	M	M	M	M
1987	M	M	M	M	M	M	M	M	M	M	M	M
1988	M	M	M	M	M	M	M	M	M	M	M	M
1989	M	M	M	M	M	M	M	M	M	M	M	M
1990	M	M	17.4	17.6	16.6	15.8	13.4	11.2	10.6	11.9	15.6	11.7
1991	14.6	16.3	17.2	18.0	18.9	17.0	14.6	12.9	13.9	12.2	11.8	11.6
1992	13.4	15.7	18.4	18.7	15.9	16.7	14.0	14.0	13.3	13.9	12.6	12.6
1993	15.5	15.6	17.2	18.2	14.9	16.3	13.9	13.8	12.5	13.1	13.6	13.4
1994	13.5	18.0	18.4	17.8	19.6	16.2	14.4	12.1	13.7	13.1	12.7	13.3
1995	14.0	16.9	14.1	15.3	17.5	15.5	13.0	8.6	11.7	10.1	11.6	11.8
1996	11.1	15.0	16.3	17.8	16.2	14.0	10.8	10.7	12.0	12.3	11.9	11.9
1997	11.6	15.0	15.7	17.1	18.6	15.8	14.4	14.6	12.9	11.6	13.9	15.5
1998	16.2	16.0	20.5	18.6	15.1	14.7	13.9	11.4	12.6	13.3	13.3	12.2
1999	13.3	11.7	15.5	16.6	17.4	15.1	11.7	8.7	10.2	9.8	9.5	9.0
2000	10.6	13.3	12.9	15.7	16.2	14.6	13.1	12.0	11.4	12.2	10.5	13.8
2001	13.5	13.2	18.3	17.7	1.8	7.6	4.8	14.9	14.8	13.6	13.3	13.2
2002	12.5	14.7	15.1	13.1	15.9	15.2	13.8	14.0	12.9	13.9	13.0	14.0
2003	14.8	17.2	16.8	17.7	17.8	15.2	13.1	11.5	10.7	11.3	12.2	13.2
2004	10.5	13.7	14.8	15.1	14.8	14.1	12.2	12.0	10.3	10.1	10.0	8.7
2005	9.1	9.7	8.8	16.1	13.3	13.2	10.2	10.2	10.2	9.9	11.1	9.4
2006	10.1	12.3	13.4	13.7	12.8	13.6	12.1	11.2	10.7	11.1	11.6	11.8
2007	12.9	13.6	15.0	14.9	15.3	13.1	12.3	9.8	10.1	11.8	12.7	10.3
2008	10.9	11.7	13.7	14.7	14.8	13.7	10.7	8.9	7.1	8.8	9.1	7.3
2009	M	M	M	M	M	M	M	M	M	M	M	M
2010	M	M	M	M	M	M	M	M	M	M	M	M
2011	M	M	M	M	M	M	13.7	8.5	6.9	8.4	5.7	0.7
2012	0.0	1.3	13.8	13.3	14.3	15.8	12.8	10.2	10.0	8.5	8.9	7.9
2013	9.8	10.9	13.9	14.6	0.7	0.0	0.0	0.0	0.0	0.0	0.0	0.0
2014	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.1	0.0	0.0	0.0
2015	0.1	0.0	0.0	0.1	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0
2016	0.0	0.0	0.2	0.0	0.0	0.0	0.0	0.0	6.5	11.3	M	0.0
2017	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.6	0.4	0.0	0.0
2018	0.0	0.0	M	0.0	0.0	0.0	0.0	0.0	0.2	0.0	0.0	0.0
2019	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	9.7
2020	5.8	15.0	14.2	17.0	18.0	12.7	11.9	10.1	7.7	11.2	13.0	8.8
2021	0.0	0.0	8.7	13.7	15.1	13.0	11.9	9.9	10.3	13.3	11.8	11.6
2022	11.8	12.4	13.9	16.8	16.0	13.6	12.2	9.5	9.3	12.7	12.1	10.8
2023	13.1	14.2	16.1	16.7	18.0	14.6	13.1	10.7	12.0	12.2	M	M
2024	13.9	13.6	15.1	M	M	12.1	10.2	9.7	9.8	11.5	10.6	M

Average Daily High Temperature [F]

Year	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
1980	M	M	M	M	83.78	86.00	85.80	86.94	88.00	88.31	86.22	M
1981	M	M	88.58	86.95	88.89	86.75	88.11	89.03	89.20	89.67	91.50	M
1982	84.68	82.80	84.88	87.96	90.17	84.86	86.73	88.20	89.10	89.46	87.83	M
1983	M	M	88.50	90.15	88.43	89.57	88.53	89.67	90.50	90.04	89.30	86.81
1984	86.00	87.21	86.89	89.22	88.86	89.12	88.21	88.90	90.30	89.55	87.42	M
1985	M	M	85.22	88.00	M	M	M	M	M	M	M	M
1986	M	M	M	M	M	M	M	M	M	M	M	M
1987	M	M	M	M	M	M	M	M	M	M	M	M
1988	M	M	M	M	M	M	M	M	M	M	M	M
1989	M	M	M	M	M	M	M	M	M	M	M	M
1990	M	M	87.60	90.34	90.10	88.63	89.16	89.29	92.00	90.79	89.62	86.63
1991	84.77	87.26	88.27	88.97	90.58	89.17	88.45	88.55	88.86	87.76	85.57	82.90
1992	83.54	83.69	86.23	89.52	89.87	87.27	86.31	86.48	86.60	87.26	84.62	84.32
1993	83.48	85.41	87.00	89.30	90.10	87.97	87.81	86.97	88.80	88.55	86.03	84.53
1994	84.55	84.68	86.74	88.03	89.32	87.93	86.96	88.46	90.10	89.61	88.00	86.48
1995	86.32	87.71	88.48	89.67	90.06	87.93	88.32	88.74	89.90	88.68	87.20	86.19
1996	84.55	85.72	85.68	88.30	88.29	85.79	87.35	89.26	90.53	89.81	87.80	86.32
1997	83.94	82.64	84.26	87.73	90.26	88.40	89.19	90.60	91.87	91.13	90.27	88.23
1998	89.16	89.32	89.52	90.90	90.42	89.07	88.33	91.61	91.23	90.44	89.25	87.67
1999	86.43	84.89	88.50	89.70	90.84	89.80	90.68	89.63	90.37	89.61	89.24	85.08
2000	84.40	85.52	85.62	85.47	88.32	87.37	88.68	89.23	90.34	89.42	88.07	85.90
2001	85.94	84.16	87.61	88.60	90.45	89.73	88.18	90.00	91.68	91.07	90.23	87.81
2002	85.74	86.61	87.95	88.80	87.94	88.60	87.90	90.45	92.37	90.58	89.37	87.65
2003	87.95	88.90	89.97	91.71	90.50	89.03	89.21	91.96	92.62	92.14	91.39	87.65
2004	M	M	M	M	M	M	M	M	M	M	M	M
2005	M	M	M	M	M	M	M	M	M	M	M	M
2006	M	M	M	M	M	M	M	M	M	M	M	M
2007	M	85.61	M	M	M	M	M	M	M	M	M	M
2008	M	M	M	M	M	M	M	M	M	M	M	M
2009	M	74.30	M	87.80	M	M	M	M	M	M	M	M
2010	78.80	M	M	M	87.80	M	M	91.15	91.58	90.70	87.20	86.17
2011	84.51	81.72	81.28	85.40	85.61	84.85	87.73	87.80	93.08	91.46	89.97	90.24
2012	87.16	87.74	87.80	89.60	90.20	89.00	90.12	90.35	92.72	93.78	91.88	87.02
2013	87.45	87.93	90.30	91.03	91.69	90.16	91.28	92.21	93.32	93.20	90.92	87.68
2014	87.97	88.31	89.77	90.32	92.04	92.30	92.27	92.33	93.08	93.03	92.42	92.39
2015	90.47	91.21	90.35	90.62	89.60	89.12	89.72	92.79	93.98	93.49	91.82	91.57
2016	92.21	93.08	92.79	92.06	91.81	91.64	91.63	92.33	92.96	92.06	81.84	90.65
2017	85.74	88.95	91.75	89.92	91.05	87.10	88.40	91.40	91.59	89.38	88.20	86.51
2018	85.87	86.60	86.90	90.05	88.70	87.80	89.84	90.64	91.64	92.48	90.56	90.38
2019	91.46	90.13	94.72	90.86	91.05	89.90	90.47	90.98	91.76	92.15	91.34	92.97
2020	91.86	92.58	91.82	93.86	94.54	94.65	94.94	94.94	95.65	95.75	94.16	92.35
2021	89.60	89.60	91.53	92.86	93.37	92.75	93.32	94.07	95.72	92.89	93.45	91.23
2022	89.19	90.56	89.60	92.14	92.74	93.14	92.21	94.25	95.43	94.88	90.78	89.60
2023	90.37	88.35	91.28	92.24	94.76	94.82	90.98	96.14	97.40	97.54	M	M
2024	92.70	94.38	93.69	M	82.40	94.23	95.23	97.38	97.22	96.99	96.54	M

Average Daily Low Temperature [F]

Year	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
1980	M	M	M	M	77.00	77.67	76.84	77.94	82.00	77.25	75.91	M
1981	M	M	75.92	76.74	78.61	78.08	77.33	78.38	79.10	79.67	79.00	M
1982	75.42	78.00	74.46	76.84	78.06	76.86	77.55	78.15	80.90	79.08	79.43	M
1983	M	M	76.00	78.38	78.70	78.18	78.80	77.73	78.83	78.23	77.53	75.77
1984	75.16	75.04	74.59	75.19	77.57	78.82	77.66	77.52	78.00	78.14	76.83	M
1985	M	M	79.00	76.70	M	M	M	M	M	M	M	M
1986	M	M	M	M	M	M	M	M	M	M	M	M
1987	M	M	M	M	M	M	M	M	M	M	M	M
1988	M	M	M	M	M	M	M	M	M	M	M	M
1989	M	M	M	M	M	M	M	M	M	M	M	M
1990	M	M	76.48	77.79	78.13	78.10	77.87	77.32	79.89	80.46	78.93	75.85
1991	74.73	75.56	75.93	76.80	78.52	78.43	77.21	76.77	77.21	75.79	74.27	73.84
1992	73.39	73.14	73.52	76.81	78.48	77.27	75.41	72.77	75.43	76.00	73.59	72.97
1993	72.55	72.89	73.39	76.00	76.55	77.07	76.35	76.35	76.80	76.65	75.80	74.33
1994	73.06	71.68	74.61	75.77	77.00	77.27	77.00	76.86	78.45	78.16	77.37	75.29
1995	74.48	74.36	76.10	77.03	77.97	77.60	76.74	76.23	78.33	76.55	75.53	74.55
1996	72.19	74.00	73.81	76.27	77.71	76.36	76.26	77.65	78.60	79.29	76.73	75.03
1997	73.23	73.00	72.35	75.17	76.71	76.80	77.32	78.30	79.33	79.13	78.13	75.32
1998	75.10	76.11	75.94	78.13	78.35	77.03	75.83	78.68	79.14	78.00	77.21	75.57
1999	74.93	73.89	75.07	76.37	76.81	77.60	78.23	77.23	78.00	77.19	77.00	75.08
2000	73.33	74.21	73.27	73.93	76.48	77.17	76.90	77.45	78.52	77.26	76.10	74.90
2001	73.87	72.68	73.94	74.17	77.58	77.73	78.38	80.64	80.32	79.93	78.96	77.87
2002	74.68	74.26	77.33	77.20	76.03	76.87	76.29	77.74	80.37	79.61	77.33	75.88
2003	73.77	74.22	73.72	77.41	76.52	75.79	77.01	78.10	77.77	78.55	77.13	76.11
2004	M	M	M	M	M	M	M	M	M	M	M	M
2005	M	M	M	M	M	M	M	M	M	M	M	M
2006	M	M	M	M	M	M	M	M	M	M	M	M
2007	M	76.57	M	M	M	M	M	M	M	M	M	M
2008	M	M	M	M	M	M	M	M	M	M	M	M
2009	M	74.30	M	87.80	M	M	M	M	M	M	M	M
2010	78.80	M	M	M	87.80	M	M	78.24	76.46	77.23	76.58	74.74
2011	74.52	76.85	77.00	78.73	80.76	80.68	80.60	81.54	78.74	78.22	77.90	76.48
2012	74.68	74.21	74.62	75.14	76.42	76.04	76.01	75.72	78.56	79.79	78.26	76.48
2013	75.43	75.07	76.77	77.06	77.70	77.60	77.41	77.64	79.22	78.63	76.46	75.78
2014	74.10	74.62	75.32	75.92	77.81	79.22	78.45	78.51	78.92	78.86	78.92	78.68
2015	77.70	77.51	76.42	75.26	75.72	77.00	77.23	78.16	78.86	79.26	78.14	78.16
2016	76.48	75.45	77.81	75.92	77.58	77.96	77.17	77.29	76.10	78.23	81.61	77.29
2017	78.80	77.79	77.23	77.64	78.22	78.49	79.85	77.99	78.55	79.09	79.90	80.47
2018	82.14	82.04	86.90	80.60	78.80	80.60	80.24	78.38	77.48	78.62	77.90	77.78
2019	78.68	77.73	76.72	77.84	77.75	77.06	77.58	76.76	78.74	76.83	78.86	71.83
2020	72.88	66.51	66.80	68.48	67.77	68.83	69.10	69.98	71.96	71.25	67.58	69.89
2021	89.60	89.60	68.90	67.74	67.94	67.55	69.32	69.05	71.84	71.91	68.62	66.78
2022	67.19	66.33	68.69	69.74	69.22	70.06	68.58	69.86	71.10	69.74	70.17	66.90
2023	66.97	67.72	67.04	68.96	70.76	70.16	73.33	71.66	71.54	75.84	M	M
2024	68.20	69.66	67.35	M	82.40	70.31	69.39	70.55	71.25	71.91	70.06	M

Average Daily Temperature (high+low)/2 [F]

Year	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
1980	M	M	M	M	80.39	81.83	81.32	82.44	85.00	82.78	81.07	M
1981	M	M	82.25	81.84	83.75	82.42	82.72	83.71	84.15	84.67	85.25	M
1982	80.05	80.40	79.67	82.40	84.11	80.86	82.14	83.17	85.00	84.27	83.63	M
1983	M	M	82.25	84.27	83.57	83.88	83.67	83.70	84.67	84.13	83.42	81.29
1984	80.58	81.12	80.74	82.20	83.21	83.97	82.93	83.21	84.15	83.84	82.12	M
1985	M	M	82.11	82.35	M	M	M	M	M	M	M	M
1986	M	M	M	M	M	M	M	M	M	M	M	M
1987	M	M	M	M	M	M	M	M	M	M	M	M
1988	M	M	M	M	M	M	M	M	M	M	M	M
1989	M	M	M	M	M	M	M	M	M	M	M	M
1990	M	M	82.04	84.07	84.11	83.37	83.52	83.31	85.95	85.62	84.28	81.24
1991	79.75	81.41	82.10	82.88	84.55	83.80	82.83	82.66	83.03	81.78	79.92	78.37
1992	78.46	78.41	79.87	83.17	84.18	82.27	80.86	79.63	81.02	81.63	79.10	78.65
1993	78.02	79.15	80.19	82.65	83.32	82.52	82.08	81.66	82.80	82.60	80.92	79.43
1994	78.81	78.18	80.68	81.90	83.16	82.60	81.98	82.66	84.28	83.89	82.68	80.89
1995	80.40	81.04	82.29	83.35	84.02	82.77	82.53	82.48	84.12	82.61	81.37	80.37
1996	78.37	79.86	79.74	82.28	83.00	81.07	81.81	83.45	84.57	84.55	82.27	80.68
1997	78.58	77.82	78.31	81.45	83.48	82.60	83.26	84.45	85.60	85.13	84.20	81.77
1998	82.13	82.71	82.73	84.52	84.39	83.05	82.08	85.15	85.18	84.22	83.23	81.62
1999	80.68	79.39	81.78	83.03	83.82	83.70	84.45	83.43	84.18	83.40	83.12	80.08
2000	78.87	79.86	79.44	79.70	82.40	82.27	82.79	83.34	84.43	83.34	82.09	80.40
2001	79.90	78.42	80.77	81.38	84.02	83.73	83.28	85.32	86.00	85.50	84.60	82.84
2002	80.21	80.44	82.64	83.00	81.98	82.73	82.10	84.10	86.37	85.10	83.35	81.76
2003	80.86	81.56	81.85	84.56	83.51	82.41	83.11	85.03	85.19	85.34	84.26	81.88
2004	M	M	M	M	M	M	M	M	M	M	M	M
2005	M	M	M	M	M	M	M	M	M	M	M	M
2006	M	M	M	M	M	M	M	M	M	M	M	M
2007	M	81.09	M	M	M	M	M	M	M	M	M	M
2008	M	M	M	M	M	M	M	M	M	M	M	M
2009	M	74.30	M	87.80	M	M	M	M	M	M	M	M
2010	78.80	M	M	M	87.80	M	M	84.70	84.02	83.97	81.89	80.45
2011	79.51	79.29	79.14	82.07	83.18	82.77	84.16	84.67	85.91	84.84	83.98	83.36
2012	80.92	80.95	81.21	82.37	83.30	82.52	83.07	83.04	85.64	86.78	85.07	81.74
2013	81.44	81.50	83.53	84.04	84.69	83.86	84.35	84.93	86.27	85.91	83.69	81.73
2014	81.04	81.47	82.55	83.12	84.93	85.76	85.36	85.42	86.00	85.94	85.67	85.54
2015	84.08	84.36	83.39	82.94	82.66	83.06	83.47	85.48	86.42	86.38	84.98	84.87
2016	84.35	84.26	85.30	83.99	84.69	84.80	84.40	84.81	84.53	85.15	81.72	83.97
2017	82.27	83.37	84.49	83.78	84.64	82.79	84.13	84.69	85.07	84.24	84.05	83.49
2018	84.01	84.32	86.90	85.32	83.75	84.20	85.04	84.51	84.56	85.55	84.23	84.08
2019	85.07	83.93	85.72	84.35	84.40	83.48	84.03	83.87	85.25	84.49	85.10	82.40
2020	82.37	79.54	79.31	81.17	81.15	81.74	82.02	82.46	83.80	83.50	80.87	81.12
2021	89.60	89.60	80.21	80.30	80.66	80.15	81.32	81.56	83.78	82.40	81.03	79.00
2022	78.19	78.45	79.15	80.94	80.98	81.60	80.40	82.05	83.27	82.31	80.48	78.25
2023	78.67	78.04	79.16	80.60	82.76	82.49	82.16	83.90	84.47	86.69	M	M
2024	80.45	82.02	80.52	M	82.40	82.27	82.31	83.97	84.23	84.45	83.30	M

Average Relative Humidity [%]

This value is computed via a simple average of available observations weighted by the duration between observations.

Year	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
1980	M	M	M	M	80.3%	79.3%	82.9%	88.1%	73.2%	84.8%	85.1%	M
1981	M	M	77.6%	85.2%	81.0%	85.5%	85.4%	87.6%	84.3%	80.6%	73.8%	M
1982	83.1%	86.2%	86.8%	85.1%	79.7%	88.3%	83.2%	82.0%	82.5%	85.1%	83.9%	M
1983	M	M	79.7%	83.8%	84.5%	82.3%	80.3%	78.8%	79.2%	80.4%	80.4%	82.0%
1984	81.7%	81.3%	82.0%	79.6%	81.0%	86.4%	83.5%	84.6%	82.0%	83.2%	87.7%	M
1985	M	M	72.7%	81.0%	M	M	M	M	M	M	M	M
1986	M	M	M	M	M	M	M	M	M	M	M	M
1987	M	M	M	M	M	M	M	M	M	M	M	M
1988	M	M	M	M	M	M	M	M	M	M	M	M
1989	M	M	M	M	M	M	M	M	M	M	M	M
1990	M	M	85.5%	84.5%	87.1%	88.3%	88.6%	88.5%	84.1%	84.4%	84.5%	88.1%
1991	87.5%	84.6%	85.0%	85.7%	85.5%	85.3%	83.6%	82.8%	78.0%	75.0%	82.1%	87.3%
1992	83.0%	81.5%	79.2%	78.5%	83.2%	88.1%	87.8%	87.0%	87.6%	87.1%	89.9%	85.6%
1993	82.7%	78.6%	82.2%	85.6%	87.8%	88.2%	88.4%	87.0%	87.1%	86.5%	86.2%	88.7%
1994	89.3%	87.1%	87.4%	89.2%	88.5%	81.0%	82.5%	81.4%	79.7%	81.6%	84.3%	84.2%
1995	82.7%	80.5%	80.2%	71.4%	75.5%	76.9%	79.2%	80.0%	76.2%	87.6%	86.8%	87.8%
1996	86.3%	86.3%	87.0%	85.0%	85.7%	86.9%	89.3%	87.7%	86.4%	86.7%	89.6%	88.5%
1997	89.5%	92.1%	89.9%	82.8%	77.6%	87.6%	88.5%	88.5%	87.4%	87.2%	88.3%	88.6%
1998	88.6%	89.2%	88.8%	75.4%	76.1%	78.7%	79.0%	73.5%	73.9%	72.7%	74.7%	77.2%
1999	88.3%	88.8%	88.0%	86.8%	84.5%	86.8%	84.8%	77.0%	72.2%	74.4%	75.6%	75.9%
2000	71.9%	73.4%	71.4%	72.2%	74.7%	75.9%	74.7%	76.9%	78.7%	87.0%	89.6%	90.3%
2001	87.9%	80.0%	78.4%	80.0%	79.8%	82.6%	83.9%	83.0%	81.3%	81.4%	82.5%	87.0%
2002	86.6%	83.1%	81.1%	79.9%	81.4%	81.9%	81.9%	83.2%	84.8%	84.6%	86.1%	85.3%
2003	82.5%	83.5%	84.5%	86.0%	88.0%	88.5%	87.3%	85.0%	83.8%	84.6%	86.1%	87.4%
2004	86.5%	84.0%	83.4%	83.7%	87.7%	86.4%	80.6%	83.2%	80.2%	80.4%	83.1%	82.9%
2005	84.3%	80.5%	77.4%	78.8%	76.7%	80.0%	80.1%	78.1%	83.5%	85.5%	85.6%	86.4%
2006	87.2%	83.9%	78.0%	77.0%	77.6%	81.2%	82.5%	80.6%	82.1%	84.5%	84.0%	85.9%
2007	85.4%	81.5%	83.1%	80.4%	80.5%	83.7%	82.0%	82.2%	82.5%	81.4%	82.7%	85.4%
2008	83.7%	84.1%	79.5%	83.1%	82.4%	80.0%	84.0%	83.0%	82.2%	82.7%	82.9%	84.6%
2009	M	M	M	M	M	M	M	M	M	M	M	M
2010	M	M	M	M	M	M	M	M	M	M	M	M
2011	M	M	M	M	M	M	71.3%	72.9%	74.3%	78.7%	81.5%	82.7%
2012	M	65.7%	74.8%	69.2%	67.1%	66.6%	67.6%	67.7%	71.9%	76.2%	82.1%	86.3%
2013	79.2%	77.3%	76.0%	75.8%	76.6%	M	M	M	M	M	78.9%	M
2014	M	M	M	M	M	M	M	66.8%	75.2%	M	M	M
2015	66.2%	M	M	74.6%	M	M	M	M	M	M	M	M
2016	M	M	M	M	M	72.3%	M	M	73.7%	71.7%	M	M
2017	M	53.5%	M	59.4%	M	M	M	M	72.4%	70.8%	M	M
2018	76.6%	74.4%	M	74.3%	74.6%	82.2%	77.4%	77.0%	76.9%	75.7%	78.4%	79.6%
2019	76.8%	78.5%	76.9%	75.7%	76.9%	77.9%	77.0%	75.4%	74.1%	76.7%	75.7%	79.1%
2020	78.8%	76.4%	74.4%	73.7%	76.1%	75.8%	77.2%	75.2%	72.3%	74.3%	75.1%	75.6%
2021	62.7%	62.7%	75.8%	74.1%	78.6%	81.2%	81.0%	80.0%	75.0%	76.7%	78.7%	83.7%
2022	81.5%	80.2%	80.1%	77.7%	77.9%	77.4%	82.7%	78.6%	78.6%	77.2%	83.9%	82.1%
2023	82.4%	76.9%	75.8%	76.5%	76.4%	79.1%	80.9%	76.2%	72.9%	73.5%	M	M
2024	78.6%	75.7%	77.0%	M	M	82.6%	81.0%	75.3%	76.4%	74.2%	75.3%	M