The stats tab provides useful information in gauging the overall situation in the game.
Player Listed both the individual nations and the entire alliance (if there are multiple nations)
PUs Lists the current number of IPCs
Production Is the total of the area values held. It does not include national objectives. It does not adjust for AI bonuses (look under the Economy tab for that.
Units The total number of units (including factories and AA guns)
TUV stands for Total Unit Value. All units are valued at production cost. Non-buildable units are ignored
VC is the number of victory cities held
Below the first table is a technology achievement table.