[I have been implementing a LEAPS strategy with ACWI for the past year using these calculations in a spreadsheet](https://imgur.com/a/jh0r1l7). The research I've done on similar strategies say that I need to account for the implied interest and forgone dividends when buying options on the index, and that the total cost should be compared to a benchmark rate.
Are the calculations I am doing correct? If so, I don't really get why buying a similarly leveraged option now with fewer DTE results in a much higher total cost vs the benchmark.
