Books Written
Total Wordcount:
$$T_w = 157049+144413+148903+143651+153099+142305+147213+122734+152793+119529+129626+114779+126300+179608+157394+173438+145141+118867+71227+156726 = 2804795\text{ words}$$
Total Time:
$$T_t = \text{February 26, 2013}-\text{March 1, 1992} \approx 20.993 \text{ years}$$
Writing Speed:
$$
\frac{\text{Total Wordcount}}{\text{Total Time}} = \frac{T_w}{T_t} \approx 133604.114 \frac{\text{Words}}{\text{Year}} \approx 11133.676 \frac{\text{Words}}{\text{Month}} \\ \approx 2560.572 \frac{\text{Words}}{\text{Week}} \approx 365.796 \frac{\text{Words}}{\text{Day}} \approx 15.241 \frac{\text{Words}}{\text{Hour}}
$$