Good day,

I am working on my thesis, and I have separate variables from OECD on excel sheets. Individually, the variables are already in a panel format. The problem is that sheets only show data from the years available even though I have a filter from 1985 until 2019 (i.e. I have GDP growth from 1985 until 2019 for a certain country, but the same country's interest rates data is only from 1990 until 2019). I find that severely problematic because I do not know how to prepare a database due to mismatches if I want to put all sheets in one. I was wondering if there are any commands in Stata with which I can circumvent this problem?

I attached an image of the excel sheets combined to visualize my difficulty.
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