All Global Patties contain scientifically formulated vitamins, minerals and fats specifically selected, balanced and tested for optimal bee nutrition.
The amount of pollen in Global pollen patties does not determine the nutritional or protein value, but in fact, the consumption rate.  Depending on how strong your hives are and how fast you want the hive brood to build up, will determine what percentage you should be feeding. At 4% you will have a slower consumption rate, and a steady-build up. At 15% you have a much faster build-up but much faster consumption rate as well, meaning you will have to feed more often. 
In the Spring, we recommend 15% for a faster build-up so that the hive is strong and ready for the honey flow. However, if you start feeding early then 4% would be sufficient for a steady-build up until natural pollen is available.
In the Fall, 4% patties is a sufficient amount of pollen to have a steady consumption rate to build up strong winter bees.