I've attched some very handy nutrient calculators that help estimate nitrogen and sulphur as well as economic response to phosphorus and a few other good ones. Enjoy!!!
Nitrogen and sulphur calculator: http://beyondagronomy.com//cmsFiles/documents/document5a186e4fca093.xlsx
Seedrow fertilizer safety calculator: http://beyondagronomy.com//cmsFiles/documents/document5a18702be208e.xls
Yield potential calcualtor based on stored soil moisture and rainfall: http://beyondagronomy.com//cmsFiles/documents/document5a18712e6fe3d.xls
Phosphate economic return calculator: http://beyondagronomy.com//cmsFiles/documents/document5a18717ad3190.xls
Big thanks to Dr. Rigas Karamanos for the handy calculators!