add y axis label to normalization chart

dashboard.Rmd

@@ -388,8 +388,12 @@ output$cost_index_chart <- renderDygraph({
   
   if (selected_scale == "Index") {
     value_columns <- paste0(selected_methods, " Index")
+    
+    y_label <- "Cost Index"
   } else if (selected_scale == "Loss") {
     value_columns <- paste0(selected_methods, " Loss")
+    
+    y_label <- "Normalized Loss"
   }
   
   normalization_index <- normalized_data %>% 
@@ -414,7 +418,7 @@ output$cost_index_chart <- renderDygraph({
     select(-normalization_year) %>% 
     xts(order.by = normalization_index$normalization_year)
   
-  dygraph(normalization_index_ts) %>%
+  dygraph(normalization_index_ts, ylab = y_label) %>%
     dyOptions(
       colors = paletteer_d("ggthemes::Classic_Purple_Gray_12", ncol(normalization_index - 1)),
       fillGraph = T,