To figure out what your score would be in 2050, you cant just take your current increase and multiply it by the turns remaining. To continue to get 35 points per turn, you would need to continue expanding and having your population increase at the same rate too. If you just took the empire you have now, without changing it until 2050, your increase per turn would slowly dwindle away.

TotalPastScore = CurrentOverallScore * TurnsPlayed

CurrentTurnScore = (TurnsPlayed * Increase) + CurrentOverallScore

2050_OverallScore = (TotalPastScore + (CurrentTurnScore * TurnsRemaining)) / 540

In your game, your score is 4410 with 179 turns remaining and a 35 point per turn increase.

CurrentOverallScore = 4410

TurnsRemaining = 179

TurnsPlayed = 540 - 179 = 361

Increase = 35

TotalPastScore = 4410 * 361 = 1592010

CurrentTurnScore = (361 * 35) + 4410 = 17045

2050_OverallScore = (1592010 + (17045 * 179)) / 540 = 8598

8598 would be your score in 2050 if your population and territory stayed the same until then (and if my math was right). SirPleb posted an

Excel spreadsheet on another thread that handles the calculations. I'm just assuming he uses the same formula, as I don't have Excel to check out how he did it.