How to analyse time series data NIFTY50

 How to analyze data( NIFTY50)

getSymbols("^NSEI", from="2004-01-01", to=Sys.Date())
chartSeries(Cl(NSEI))
> ret <- dailyReturn(Cl(NSEI), type='log')
Warning message:
In to_period(xx, period = on.opts[[period]], ...) :
  missing values removed from data
> par(mfrow=c(2,2))
> acf(ret, main="Return ACF");
> pacf(ret, main="Return PACF");
> acf(ret^2, main="Squared return ACF");
> pacf(ret^2, main="Squared return PACF")
> par(mfrow=c(1,1))
> m=mean(ret);s=sd(ret);
> par(mfrow=c(1,2))
> hist(ret, nclass=40, freq=FALSE, main='Return histogram');curve(dnorm(x,
+          mean=m,sd=s), from = -0.3, to = 0.2, add=TRUE, col="red")
> plot(density(ret), main='Return empirical distribution');curve(dnorm(x,
+         mean=m,sd=s), from = -0.3, to = 0.2, add=TRUE, col="red")
> par(mfrow=c(1,1))

> kurtosis(ret)
[1] 12.6355
attr(,"method")
[1] "excess"
> plot(density(ret), main='Return EDF - upper tail', xlim = c(0.1, 0.2),
+      ylim=c(0,2));
> curve(dnorm(x, mean=m,sd=s), from = -0.3, to = 0.2, add=TRUE, col="red")
> plot(density(ret), xlim=c(-5*s,5*s),log='y', main='Density on log-scale')
Warning message:
In xy.coords(x, y, xlabel, ylabel, log) :
  75 y values <= 0 omitted from logarithmic plot
> curve(dnorm(x, mean=m,sd=s), from=-5*s, to=5*s, log="y", add=TRUE,
+       col="red")

> qqnorm(ret);qqline(ret);