Monthly visitor numbers, in thousands, for an attraction are shown below.
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Visitors | 44 | 46 | 52 | 60 | 71 | 84 | 109 | 103 | 76 | 64 | 50 | 45 |
An analyst estimates the annual total as 12×109=130812\times109=130812×109=1308 thousand by using July as a typical month.
Calculate the actual annual total from the supplied data.
Calculate the amount by which the analyst's estimate exceeds the actual total.
Explain the main weakness in the analyst's method.
State one check that should be carried out before the monthly values are used.