Format for Earthquake Summary Data
July 1962 - Present
| Column | Format | Description |
| 1-2 | I2 | Year |
| 3-6 | I4 | Date in Universal Coordinated Time (UTC) |
| 8-11 | I4 | Origin time hour and minute, UTC |
| 13-17 | F5.2 | Origin time seconds |
| 19-20 | I2 | Latitude north, degrees |
| 22-26 | F5.2 | Latitude minutes |
| 28-30 | I3 | Longitude west, degrees |
| 32-36 | F5.2 | Longitude minutes |
| 39-43 | F5.2 | Depth, km, below datum, which is 1.5 km above sea level for the Utah region and 2.0 km above sea level for the Yellowstone region |
| 44 | A1 | "*" for fixed or poor quality depth |
| 45 | A1 | "W" if the magnitude is a local magnitude (ML), calculated from peak amplitudes on Wood-Anderson records; otherwise it is a coda magnitude (MC), calculated from signal durations. For pre-1981 events, some “W” magnitudes are averages of MLs and MCs. |
| 46-50 | F5.2 | Magnitude (-9.99 if unavailable) |
| 52-53 | I2 | NO, the number of P and S arrival times used in the location |
| 55-57 | I3 | GAP, the maximum azimuthal separation between recording stations used in the location, degrees |
| 58-62 | F5.1 | DMN, the horizontal distance from the epicenter to the nearest station used in the location, km |
| 63-67 | F5.2 | RMS, the weighted root-mean-square of the differences between the observed and calculated arrival times, sec |
| 68-72 | F5.1 | ERH, the horizontal standard error, km |
| 73-77 | F5.1 | ERZ, the vertical standard error, km |
| 79 | A1 | Q, location quality (if computed) |