In: Statistics and Probability
| Period | Receipts | 
| 1 | 30172000 | 
| 2 | 16916000 | 
| 3 | 11794000 | 
| 4 | 7862000 | 
| 5 | 6354000 | 
| 6 | 5222000 | 
| 7 | 4106000 | 
| 8 | 3368000 | 
| 9 | 2302000 | 
| 10 | 2440000 | 
| 11 | 2472000 | 
| 12 | 2766000 | 
| 13 | 2856000 | 
| 14 | 2300000 | 
| 15 | 1704000 | 
| 16 | 1776000 | 
| 17 | 1362000 | 
| 18 | 1158000 | 
| 19 | 1124000 | 
Use the formula for the "best" trend model to forecast the time
series (Receipts) for x = t = 20.
Round the forecast to the nearest whole number.