Backing Angles and Hip Drop
| The value of the Hip Drop is based on a unit half width for the Hip Rafter. |
| HIP DROP along ELLIPSE: SAMPLE DATA |
| x from Center | Tangent to Circle | Backing Angle | Plumb Backing Angle | Unit Hip Drop |
| 1.00000 | Undefined | 45.00000° | 90.00000° | Undefined |
| .99000 | 7.01792 | 44.42987° | 78.60665° | 4.96242 |
| .95000 | 3.04243 | 42.20238° | 65.06957° | 2.15132 |
| .90000 | 2.06474 | 39.52360° | 55.59138° | 1.45999 |
| .80000 | 1.33333 | 34.44987° | 43.31379° | .94281 |
| .70000 | .98020 | 29.66815° | 34.72606° | .69311 |
| .60000 | .75000 | 25.10409° | 27.93835° | .53033 |
| .50000 | .57735 | 20.70480° | 22.20764° | .40825 |
| .40000 | .43644 | 16.43008° | 17.15073° | .30861 |
| .30000 | .31449 | 12.24749° | 12.53731° | .22238 |
| .20000 | .20412 | 8.12994° | 8.21305° | .14433 |
| .10000 | .10050 | 4.05466° | 4.06485° | .07106 |
| Zero | Zero | Zero | Zero | Zero |
