Summation of row based on different id and same date

[williaml]

Can you make your data reproducible next time?

FAQ: What's a reproducible example (`reprex`) and how do I create one?

Why reprex? Getting unstuck is hard. Your first step here is usually to create a reprex, or reproducible example. The goal of a reprex is to package your code, and information about your problem so that others can run it and feel your pain. Then, hopefully, folks can more easily provide a solution. What's in a Reproducible Example? Parts of a reproducible example: background information - Describe what you are trying to do. What have you already done? complete set up - include any library() calls and data to reproduce your issue. data for a reprex: Here's a discussion on setting up data for a reprex make it run - include the minimal code required to reproduce your error on the data…

Your data:

library(tidyverse)
NewData <- tibble::tribble(
  ~gvkey,        ~date,          ~a,          ~b,
            1L, "01/01/2000",    15624000, 10011531920,
            1L, "02/01/2000",    18480000, 10592724720,
            1L, "03/01/2000",    16968000, 10160611743,
            2L, "01/01/2000",  9375333997, 10011531920,
            2L, "02/01/2000",  9943536057, 10592724720,
            2L, "03/01/2000",  9470034340, 10160611743,
            3L, "01/01/2000", 441665123.3, 10011531920,
            3L, "02/01/2000", 412041243.1, 10592724720,
            3L, "03/01/2000", 417427403.1, 10160611743
  )

a<-NewData %>%
mutate(firmMarket=NewData$cshoc*NewData$prccd)

Which column is meant to be cschoc and which one is meant to be prccd? Are they from somewhere else?