Specific Gravity of Water Using Steam Table

I am not sure if I am doing this right, but I am trying to obtain the specific gravity of water at 125 DegF at a pressure of 75 PSIA.

I head over to my steam table, and have two choices, first I use the Temperature column and go to 125 DegF and obtain the ft^3/lb number. I then take the inverse of the ft^3/lb number to obtain the density. I then divide this density by 62.4 (Density of water at 60DegF) to obtain the Specific Gravity.

Or, I head over the Pressure column of the steam table and look for 75 PSIA, then obtain the ft^3/lb number and repeat the steps above.

Each of these yields a different Specific Gravity number, what the heck? What am I missing?
 
At STP (or sea level), water has a specific gravity of 1.000. When heated to 100 degrees Celsius and pressurized to one atmosphere, water has a specific gravity of 0.958. This demonstrates that an increase in both temperature and pressure causes water to lose density. This is because, at higher temperatures, water molecules gain kinetic energy and spread out, resulting in a less dense liquid.
 
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