APPENDIX TABLE 1.
SAMPLE STATISTICS OF FORT CHARACTERISTICS
| Variables | Mean | Maximum | Minimum |
|---|---|---|---|
| Malaria | |||
| Average strength (n) | 165 | 713 | 7 |
| Incidence rate of malarial fevers | 0.2971 | 3.2158 | 0 |
| Intermittent fever | 0.2473 | 3.2086 | 0 |
| Remittent fever | 0.0498 | 0.9600 | 0 |
| Monthly temperature (°F) | |||
| January to March | 36.29 | 72.98 | 3.98 |
| April to June | 62.17 | 84.29 | 43.09 |
| July to September | 71.84 | 94.48 | 44.38 |
| October to December | 44.08 | 76.78 | 17.59 |
| Monthly precipitation (inches) | |||
| January to March | 2.20 | 15.26 | 0 |
| April to June | 2.75 | 11.40 | 0 |
| July to September | 3.01 | 9.52 | 0 |
| October to December | 2.33 | 9.23 | 0 |
| Altitude around fort (feet) | |||
| Maximum | 889.26 | 4,400 | 3 |
| Minimum | 308.74 | 2,300 | −7 |
| Average | 513.23 | 2,948.90 | 0.28 |
| Standard deviation | 110.93 | 967.47 | 0.74 |
| Land improvement ratio | 0.3717 | 1.0000 | 0.0133 |
Notes: Total number of forts is 143, covering two periods: 1829–1838 and 1871–1874. The number of observations with complete malarial fevers and climate information by fort and year is 571. Malaria incidence rate is defined as the number of cases of fevers divided by average number of soldiers. Geographical features around forts are proxied by characteristics of altitude of counties where the forts were located. Land improvement ratio is the ratio of the number of acres of improved land to that of total land available for farming.