Table 11.3 Reliability Metrics Using Any Method of U.S. Distribution System by State, 2023 and 2022

  All Events (With Major Events) Without Major Events

Percent of Customers Reported SAIDI
(minutes per year)
SAIFI
(times per year)
CAIDI
(minutes per interruption)
SAIDI
(minutes per year)
SAIFI
(times per year)
CAIDI
(minutes per interruption)
Census Division
and State
Year 2023 Year 2022 Year 2023 Year 2022 Year 2023 Year 2022 Year 2023 Year 2022 Year 2023 Year 2022 Year 2023 Year 2022 Year 2023 Year 2022
New England 94.2% 96.4% 480.5 333 1.398 1.382 343.7 240.9 107.8 104.2 0.944 0.997 114.2 104.5
Connecticut 100.6% 100.2% 164.6 157.4 0.872 0.821 188.8 191.8 70.3 66.1 0.655 0.621 107.3 106.4
Maine 100.8% 102.7% 1863 963.6 3.314 3.001 562.2 321.1 247.4 216.7 1.979 1.956 125 110.8
Massachusetts 88.2% 93.1% 259.4 163.2 1.057 1.08 245.4 151 82.2 83 0.78 0.885 105.4 93.8
New Hampshire 99.3% 99.3% 645.8 616.7 1.753 1.783 368.5 345.9 124.6 107.5 0.989 0.931 126.1 115.6
Rhode Island 98.3% 98.2% 104.6 81.9 0.782 0.959 133.7 85.4 52.2 63.2 0.667 0.808 78.3 78.2
Vermont 87.0% 87.2% 744.4 963.5 2.352 2.62 316.5 367.8 221.3 267.6 1.58 1.967 140 136
Middle Atlantic 97.3% 97.0% 159.5 175.9 0.883 0.958 180.7 183.6 89.9 93.4 0.736 0.802 122.2 116.5
New Jersey 101.0% 100.9% 108.3 89.7 0.881 0.875 123 102.4 88.5 79 0.831 0.838 106.5 94.3
New York 97.7% 97.1% 120 203 0.725 0.872 165.6 232.7 70 77.6 0.586 0.666 119.4 116.5
Pennsylvania 94.4% 94.1% 252.7 200.4 1.108 1.139 228 175.9 119.2 126.1 0.878 0.968 135.8 130.4
East North Central 95.7% 95.5% 472.8 313.6 1.177 1.204 401.6 260.3 107.1 120.2 0.804 0.926 133.3 129.8
Illinois 97.8% 97.4% 208.2 90.4 0.835 0.761 249.2 118.9 56.2 59 0.605 0.645 92.9 91.4
Indiana 91.1% 91.0% 455.4 279.3 1.447 1.431 314.8 195.3 110.3 137.4 0.946 1.123 116.6 122.4
Michigan 97.4% 97.5% 1093.6 513.1 1.512 1.339 723.5 383.2 162.7 166 0.921 1.015 176.7 163.6
Ohio 96.5% 96.3% 366.2 413.2 1.252 1.517 292.5 272.4 127 144 0.918 1.121 138.4 128.4
Wisconsin 92.5% 92.1% 183 273.5 0.877 1.043 208.6 262.2 72.4 99.6 0.631 0.751 114.7 132.7
West North Central 84.9% 84.7% 213.8 194.8 1.079 1.083 198.1 179.8 85.5 89.6 0.811 0.862 105.5 104
Iowa 85.2% 84.9% 104.9 85.8 0.907 0.888 115.7 96.6 70.4 75.5 0.709 0.809 99.3 93.3
Kansas 82.5% 81.3% 283.1 178.8 1.318 1.321 214.9 135.4 101.7 108.1 0.998 1.086 101.9 99.5
Minnesota 88.7% 88.6% 126.4 273.7 0.973 1.21 129.9 226.3 73.4 82.2 0.785 0.856 93.5 96
Missouri 87.6% 87.8% 371.8 148 1.315 1.05 282.9 141 106.7 97 0.876 0.876 121.7 110.7
Nebraska 73.6% 72.7% 72.6 82.1 0.558 0.608 130.1 134.9 56.8 62.3 0.48 0.541 118.3 115.1
North Dakota 89.0% 89.1% 208.6 559.6 1.055 1.297 197.7 431.4 89.9 99.6 0.907 1.036 99.1 96.1
South Dakota 74.3% 74.1% 77 327.1 1.011 1.235 76.2 264.9 63.2 123.5 0.894 0.793 70.8 155.8
South Atlantic 96.7% 95.9% 227.4 663.7 1.344 1.655 169.3 401 117.5 125.6 1.082 1.105 108.6 113.6
Delaware 89.0% 87.1% 108.2 79.8 0.83 0.853 130.3 93.5 60.4 66.4 0.692 0.767 87.3 86.5
District of Columbia 98.9% 98.2% 71.9 33.7 0.37 0.302 194.2 111.5 33.3 26.3 0.318 0.277 104.6 95.1
Florida 100.2% 99.6% 160.1 1146.3 1.015 1.48 157.7 774.5 69.2 69.7 0.823 0.866 84.1 80.4
Georgia 89.5% 87.8% 349.2 264.3 1.885 1.695 185.2 155.9 136.8 134.6 1.357 1.316 100.8 102.3
Maryland 98.7% 98.5% 166.2 259.1 0.92 1.156 180.7 224.1 66.9 84.2 0.703 0.84 95.1 100.2
North Carolina 96.1% 94.7% 252 456.3 1.506 1.927 167.4 236.8 153.5 148.6 1.274 1.236 120.5 120.2
South Carolina 95.6% 95.7% 167.2 301.1 1.507 1.87 110.9 161 126.1 114.8 1.291 1.156 97.7 99.3
Virginia 96.8% 96.8% 221.1 593.9 1.461 1.853 151.3 320.4 159.3 187.5 1.283 1.343 124.2 139.6
West Virginia 97.8% 98.1% 751.5 1003.2 2.353 2.737 319.4 366.5 385.7 543.6 1.871 2.225 206.2 244.3
East South Central 86.8% 87.0% 715.5 349.2 2.256 2.291 317.2 152.4 168.7 175.5 1.51 1.588 111.7 110.5
Alabama 80.0% 79.3% 294.2 210.1 1.574 1.448 186.9 145.1 120.2 138.8 0.979 1.159 122.8 119.8
Kentucky 96.6% 96.6% 868.2 345.8 1.903 1.781 456.3 194.1 143.4 151.7 1.167 1.3 122.9 116.7
Mississippi 83.6% 83.5% 802.1 448.5 2.717 2.429 295.2 184.6 252.8 246.7 2.142 1.967 118 125.4
Tennessee 87.0% 88.0% 857.9 404.5 2.812 3.196 305.1 126.6 186.1 188.3 1.898 1.949 98.1 96.6
West South Central 95.1% 95.1% 579.1 237.4 1.843 1.721 314.2 138 142 154.9 1.257 1.345 113 115.2
Arkansas 89.3% 89.6% 911.2 415.5 2.102 2.11 433.4 196.9 221.7 274.7 1.54 1.77 144 155.2
Louisiana 93.6% 95.4% 584.2 304 2.124 2.077 275.1 146.4 195 246.1 1.641 1.931 118.8 127.5
Oklahoma 90.0% 90.3% 896.6 195.6 1.862 1.442 481.6 135.6 139.3 144.2 1.143 1.266 121.8 113.9
Texas 96.9% 96.5% 496.2 212 1.763 1.654 281.5 128.1 124.7 127.5 1.175 1.203 106.1 105.9
Mountain 92.8% 93.1% 120.2 155.9 0.989 1.061 121.6 147 91.7 98.5 0.863 0.916 106.3 107.5
Arizona 96.7% 96.8% 106.8 139.7 0.984 1.053 108.6 132.7 69.3 72.3 0.817 0.897 84.8 80.6
Colorado 91.8% 92.4% 99.2 141.5 0.915 1.031 108.3 137.2 88.4 96.2 0.865 0.917 102.2 105
Idaho 94.9% 94.1% 137.5 180.7 1.071 1.168 128.4 154.8 119.4 158.3 0.985 1.091 121.2 145.1
Montana 75.0% 74.6% 118.7 225.6 1.068 1.376 111.1 163.9 117.1 146.1 1.055 1.203 111 121.5
Nevada 102.7% 102.6% 138.7 195.1 0.942 0.984 147.2 198.2 81.2 77 0.745 0.722 108.9 106.7
New Mexico 90.1% 90.6% 168.9 182.6 1.242 1.166 136 156.5 132.3 129.1 0.997 1.005 132.7 128.4
Utah 88.4% 89.7% 127.1 111.3 0.916 0.887 138.7 125.5 109.8 100.4 0.879 0.854 124.9 117.5
Wyoming 75.9% 76.7% 127 170.1 0.994 1.332 127.8 127.7 96 113 0.77 1.074 124.7 105.3
Pacific Contiguous 98.6% 98.6% 294.2 242.3 1.284 1.29 229.2 187.9 144.6 148.8 1.027 1.078 140.8 138.1
California 100.2% 100.2% 346.6 198.5 1.397 1.248 248.1 159.1 152 150.5 1.086 1.127 140 133.5
Oregon 92.9% 93.2% 126.9 322.9 0.825 1.288 153.8 250.8 108 123.4 0.751 0.813 143.7 151.9
Washington 95.1% 95.0% 151.7 395.3 1.025 1.481 148 267 130.6 154.9 0.908 0.991 143.8 156.4
Pacific Noncontiguous 93.6% 93.5% 448.4 330.8 2.127 2.341 210.8 141.3 184.6 162.9 1.595 1.745 115.8 93.3
Alaska 84.5% 84.4% 374.8 575.2 2.701 3.523 138.8 163.3 325.7 334.9 2.366 3.406 137.6 98.3
Hawaii 99.9% 99.9% 491.8 187.2 1.788 1.647 275.1 113.7 148.6 105.9 1.398 1.195 106.3 88.6
U.S. Total 94.8% 94.7% 342 335.5 1.333 1.405 256.6 238.8 118.4 125.7 0.999 1.064 118.5 118.1

SAIDI = System Average Interruption Duration Index. It is the minutes of non-momentary electric interruptions, per year, the average customer experienced.
SAIFI = System Average Interruption Frequency Index. It is the number of non-momentary electric interruptions, per year, the average customer experienced.
CAIDI = Customer Average Interruption Duration Index. It is average number of minutes it takes to restore non-momentary electric interruptions.
Any method combines data from utilities that use IEEE standard with data from utilities that do not.
For utilities using the IEEE method, a Major Event Day is any day that exceeds a daily SAIDI threshold called Tmed. Tmed is a duration statistic calculated from
daily SAIDI values from the past five years. For utilities not using IEEE methods, Major Events are self-determined by the reporting utility.
Percent of Customers Reported is an estimate of the percentage of total customers covered by these metrics. The numerator is reported number of meters used on the reliability schedule,
while the denominator is the number of customers reported on the sales to ultimate customers schedule. It is possible, in some instances, for this metric to exceed 100%.
For a five minute video explanation of these metrics, go to https://youtu.be/oVH9L0fCMTU.
Source: U.S. Energy Information Administration, Form EIA-861, Annual Electric Power Industry Report.