Confirm that the stock return for Thursday is lower than other weekdays, maybe because liquidity operations by Central Bank.
- get data from Yahoo! finance
- get daily percentage return with Delt()
- store weekday and p.change data in data.container
- get mean return for each 5% quantile for each weekday suing by()
- output data and plot using Libre Calc

- Monday seems to be more volatile than other weekdays(more likely to outperform in good times and underperform in bad)
- We see largest rise and plunge in Mondays
- For the first 5%-80% Thursday seems to have larger drop than other weekdays
- Although the conclusions above are obvious and illustrative from the figure, stats and p-values can be added
- Script can not work for R with other timezone and localizations