Did Candlestick Park Cost Willie Mays 100 HRs?

This is what Pete Hamill said in his review of the new book on Mays. See Willie Mays, the Say Hey Kid. Here is what I came up with on this.

I find it hard to believe that Mays lost 100 HRs because of Candlestick. Using the Retrosheet data, I found that from 1960-71, his home HR% was 6.72%. Road, it was 5.80%. He only played part of 1972 with the Giants. His home % was 15.8% better than the road % (since 6.72/5.80 = 1.158)

For the entire NL in this period, the home HR% was 2.34% while on the road it was 2.25%. The home % is 4.2% higher than the road % (since 2.34/2.25 = 1.042).

Mays seems to have gotten more out of his home park that most players. If we give him 100 more HRs at home, his home HR% rises to 10.04%. That is about 50% better than what it really was and about 73% higher than on the road.