A downhole tool is operated to pump fluid from a subterranean formation while obtaining fluid property measurements pertaining to the pumped fluid. The downhole tool is in communication with surface equipment located at the wellsite surface. The downhole tool and/or surface equipment is operated to estimate a first linear, exponential, logarithmic, and/or other relationship between compressibility and pressure of the pumped fluid based on the fluid property measurements. The downhole tool and/or surface equipment may also be operated to estimate a second linear, exponential, logarithmic, and/or other relationship between formation volume factor and pressure of the pumped fluid based on the first relationship. The downhole tool and/or surface equipment may also be operated to measure and correct optical density of the pumped fluid based on the first relationship.