This is continuous post after debt profile and lease profile of REITs. REITs diversification is a process to reduce risk by investing in multiple income generating sources. Often it is more of qualitative factor in analysis, so how can we measure it? Personally, I quantify it through top income contribution from various sources, the smaller the value, the better.
Don't put all your eggs into one basket 1) Major Sector Contribution
Some REITs manage properties from different sectors, you could refer to Sector Contribution Weightage of REITs that I've post previously for more detail. Major sector contribution refers to the biggest sector income contribution for a REIT. How you classify REIT sector would affect this figure, if you classify REIT sectors as per my previous post, then you could take the figure from the shared google sheet as reference, just remember to update it every quarter.

2) Top Geographical Location Contribution
This is another subjective figure,

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