Heavy Metal vs Light Metal vs Leather

I am wondering how the three compare to each other numerically. I always saw Heavy Metal as being somewhere between 1.3 to 1.5 times higher in terms of armor rating than Leather and 1.1 to 1.3 times that of Light Metal. I saw the Light Metal to Leather ratio as 1.1 to 1.2. Thus a Heavy Metal armor piece of e-level 10 would offer the same protection as a Leather Armor piece of e-level 13 to 15. A E-level 10 Light Metal Armor piece would offer the same protection as a E-level 11 to 12 Leather Armor Piece (rough estimates).

Thus I also believed that a Heavy Armor Piece of E-Level 100 would offer the same protection as a Leather Armor Piece of E-level 130 to 150; for Light Metal it would be 110 to 120 (again rough estimates). The price for this of course is speed and mobility, however I am not really sure how to quantify the difference yet.

However, since there was never any real clarifications on this, others may believe that the ratios are larger. So if possible, could there be a bit more of a clarification on this?

Edit:

This is a table of how I would personally quantify the armor rating of different types in comparison to E-Level and each other.