Fertilizer formula question
 

Hello, my friends
I should have know this by now but here it goes...

The formula of my fertilizer is:
11,8N+2,7P2O5+13,7K2O+11,8CaO+3,5MgO+4,8SO3.
I'm assuming that, apart the NPK 12 3 14 (rounded), the other coeficients (12, 4 and 5, also rounded) should follow the same proportionality usage as for NPK.
Am I right?

Nitrogen and everything else are expressed as weight percentage of the elements. P & K (in the US, anyway), are expressed as weight percentage of the oxides, so the element contents are lower.

A 10-10-10, therefore, is 10% N, 4.4% P, and 8.3% K.

For other nerds out there, that came about because when such analyses were first being done, the materials were "dead burned" to the oxides for analysis.

Thanks, Ray.:)