Is There an Error in Morris Kline's Book?

[King]

Hi,

I was just reading a passage from a book by Morris Kline and he states the following:

http://img443.imageshack.us/img443/3684/kline.jpg

For the first job, I calculated the following:
900 900 1100 1100 1300 1300 1500 1500
Have I misunderstood him, or is this an error on his behalf?

 

[King]

Ignore thread. I overlooked the $1800 per year part.