vehc_year.r

# Import the dataset
vehc = read.csv("NYPD_Motor_Vehicle_Collisions.csv")

# Create a year column
v = strsplit(as.character(vehc$DATE),"/")
v1 = matrix(unlist(v), ncol=3, byrow=TRUE)
vehc$year = v1[,3]

# Aggregrate by ZIP.CODE
zip_counts = vehc %>% 
  group_by(year,ZIP.CODE) %>%
  summarize(count = n()) %>%
  select(year, ZIP.CODE, value = count) %>%
  mutate(region = as.character(ZIP.CODE))