When I calculate the EMA manually for a specific day by using (C-P)*K+P=ema Where C= close of stock today K= 2/1+n (n- periods) P= EMA for previous day I got the right figure by comparing my output with which I got from my software chart for stock analysis. But, when I run the software on next day to get the today ema I found that the ema for yesterday was changed and it is not the same as what I got on yesterday. Please explain why is this change? And what is the simple way to calculate ema by utilizing Excel Regards,
I would guess that you might not be holding "n" as a constant and linking it to all of your other EMA's from previous periods, but that's just a guess. Best, LB
=========== Could be you checked it at close; settlement price 15 minutes later is different. Or 3 different charting services can & do have 3 different EMA prices; happens all the time, indicators arent exact
Note that an EMA relies on EVERY data point from the past (with recent ones being given the highest weights) so even data points from years ago can affect the EMA values. Also check out here: http://stockcharts.com/education/IndicatorAnalysis/indic_movingAvg.html