I look at the monthly returns for SPX here: Morningstar
January February March April May June 2019 7.87 2.97 1.79 3.93 -6.58 6.89
Now, given the following data from AlphaVantage for April:
2019-04-30 1. open 2848.6299 2. high 2949.5200 3. low 2848.6299 4. close 2945.8301 5. volume 69,604,840,000
I calculate for Rate of Return:
RoR = ((2945.8301-2848.6299)/2,848.63) * 100 = 3.41%
This is different from the 3.93% we get from Morningstar.
Apparently they use Total Returns or Trailing Total Returns, I am not sure.
To calculate that, I think I would need the interest, capital gains, dividends and distributions.
Is there a way for me to calculate this return using data from AlphaVantage? Or should I go a different way?