Simple trading strategy for common man like me (13-23 or 19-31 method)

This was an accidental discovery.  But i myself is really surprised about the accuracy level of this method.

Method :

This is a simple method,  which tells you when to buy or when to sell.   13 - 23 method works well with stocks in the price range of  Rs 150  to Rs 350

For nifty,  19 - 31 method works very well.
You have to sum up  all the digits of the closing value  of (any stock   or nifty ) whichever you want to study.

Assume that you want to study nifty.

You take the closing value of nifty on any day and sum up all the digits including the decimal part of it.
If the sum is less than or equal to 19,  then BUY  next day.
If the sum of greater than or equal to 31,  then SELL next day.

eg: 

if nifty closing is  5281.20  then the sum would be  5 + 2 + 8 + 1 + 2 + 0 = 18  which is < 19.  So it is a BUY

if nifty close is  5339.75  then the sum would be 5 + 3 + 3 + 9 + 7 + 5 = 32  which is > 31,  So it is a SELL.