I got my data from Thomson Reuters Datastream. As an Input for my plot i calculated daily Returns based on the Return-Index provided by datastream. Then i plotted the Monthly and the daily Returns.(Same color = same Portfolio, Blue = Green - Red) Can differences like these occur because of data outliers, that are visible in the daily Return-Index and not in the monthly?
Also: Are there any screening recommendations regarding Datastream equity Data ? Does it make sense to exclude monthly Returns >300% if you evaluate emerging markets ?
for daily Returns : (RI(t)/ RI(t-1)) -1 monthly Returns: (RI(endofmonth t)/RI(endofmonth t-1)) -1