| Site | Min (mm) | Max (mm) | Mean (mm) | No. |
|---|---|---|---|---|
| Elms Farm Iron Age | 1187 | 1479 | 1260 | 13 |
| Ivy Chimneys, Witham IA | 1209 | 1270 | 1239 | 2 |
| British Iron Age sites | 1064 | 1483 | 1224 | 169 |
| Dutch pre-Roman material | 1120 | 1400 | 1312 | 10 |
| Elms Farm Roman | 1221 | 1496 | 1371 | 29 |
| Ivy Chimneys, Witham IA/ER | 1260 | 1402 | 1344 | 8 |
| Ivy Chimneys, Witham LR | 1116 | 1504 | 1353 | 11 |
| Chelmsford | 1210 | 1500 | 1333 | 3 |
| Colchester | 1036 | 1446 | 1279 | 18 |
| Lincoln 1st-2nd C | 1144 | 1483 | 1343 | 5 |
| Lincoln 3rd-4th C | 1212 | 1513 | 1363 | 7 |
| British Roman sites | 1036 | 1674 | 1373 | 202 |
| Dutch villa | 1300 | 1540 | 1440 | 42 |
| Dutch military 1st/2nd C | 1240 | 1630 | 1453 | 35 |
| Dutch military 3rd/4th C | 1280 | 1480 | 1395 | 14 |