USGS 1.0 Sec PSA 10% 50 years	Model X 1.0 Sec PSA 10% 50 years
Model XX 1.0 Sec PSA 10% 50 year	Model XXX 1.0 Sec PSA 10% 50 years
AB95 1.0 Sec PSA 10% 50 year

Last Changed April 15, 1999