# Удаляем кварталы, если банк уже обанкротился
```{r}
banks <- data.frame(banks_finance_sent_revoc[0,])

for (i in 1:nrow(banks_finance_sent_revoc)) {
  row <- banks_finance_sent_revoc[i,]
  if (row$Revoc_Quarter != '0') {
    quarter_year <- as.numeric(substring(row$Quarter, 1, 4))
    quarter_q <- as.numeric(substring(row$Quarter, 6, 7))
    revoc_quarter_year <- as.numeric(substring(row$Revoc_Quarter, 1, 4))
    revoc_quarter_q <- as.numeric(substring(row$Revoc_Quarter, 6, 7))
    if (quarter_year < revoc_quarter_year || (quarter_year == revoc_quarter_year && quarter_q <= revoc_quarter_q)) {
      banks <<- rbind(banks, row)
    }
  } else {
    banks <<- rbind(banks, row)
  }
}
```