You need to implement a small interest calculator on my site. Please see attachment for an overview of how the interest is calculated. Another particular thing is that the interest changes over the years according to the three attached *.xls sheets. Dependant on chosen start date in date selector the sheet that needs to be used will be chosen and calculations for the amount will all be chosen according to that sheet.
I am very experienced in javascript, and also - I had 20 years background as accountant, so I know very well how to calculate interest, and everything connected with that matter.
Your work will be finished withing maximum one day.