For those that asked for my TSP Excel Spreadsheet I found an error in the "profit-loss (monthly) tab.
This is the formula that needs to be inserted in row 51 column G, =(B51-$B$48)/ABS($B$48)
Then you need to click and drag down column G to row 73 to get the correct readings for the month.
This is the formula that needs to be inserted in row 51 column G, =(B51-$B$48)/ABS($B$48)
Then you need to click and drag down column G to row 73 to get the correct readings for the month.