input a .csv file at /data with two columns (no headers):
date,amount
like may2018.csv ...
05/19/2018,-34
05/17/2018,-12
05/17/2018,-9
05/17/2018,-12
05/17/2018,-11
05/10/2018,-8
05/09/2018,-8
05/09/2018,-8
05/08/2018,-8
05/08/2018,-28
05/08/2018,-18
05/07/2018,-8
05/05/2018,-30
05/03/2018,-31
05/02/2018,-8
05/02/2018,-8
The file name is inconsequential