diff --git a/.github/workflows/snapshot-nhsn-data.yml b/.github/workflows/snapshot-nhsn-data.yml
index 7320817..cd739fc 100644
--- a/.github/workflows/snapshot-nhsn-data.yml
+++ b/.github/workflows/snapshot-nhsn-data.yml
@@ -36,7 +36,7 @@ jobs:
       - name: Snapshot NHSN data
         run: Rscript -e "nhsn_data <- RSocrata::read.socrata('https://data.cdc.gov/resource/mpgq-jmmr.csv');
                          nhsn_data <- nhsn_data[c('jurisdiction', 'weekendingdate', 'totalconfflunewadm', 'totalconfc19newadm')];
-                         nhsn_data$weekendingdate <- substr(nhsn_data$weekendingdate, 1, 10);
+                         nhsn_data[['weekendingdate']] <- substr(nhsn_data[['weekendingdate']], 1, 10);
                          colnames(nhsn_data) <- c('Geographic aggregation', 'Week Ending Date', 'Total Influenza Admissions', 'Total COVID-19 Admissions');
                          write.csv(nhsn_data, file = '$FILE_NAME', row.names = FALSE)"
         env: