I read this tweet thread yesterday, and one of the great things in it was discovering that the Department for Transport release traffic count data for Great Britain.

When you download individual observation locations you get a csv with a few years data. I checked out the one for a street near where I live using R (code at the bottom of this post):

Traffic count data for The Loan, Loanhead. Note the y scales vary with each plot.

The obvious thing to notice is the large jump in 2010. The data download also includes meta data for each year. Count observations were made in 2001 and in 2010 and all other years are estimated. I don’t know what the count frequency is in surrounding areas, but I can imagine infilling missing data is hard. However, it does look like the DfT model could do with some work, based on this anecdote

Following download, the above plot was made using the following 10 lines of R code:

library(tidyr)
library(dplyr)
library(ggplot2)

x = read.csv("~/Downloads/80158.csv")

x %>%
   select(AADFYear, PedalCycles, Motorcycles, CarsTaxis, BusesCoaches, LightGoodsVehicles, AllHGVs) %>%
   gather(Vehicle, Count, -AADFYear) %>%
   ggplot(aes(AADFYear, Count)) +
   geom_point() +
   facet_wrap(~Vehicle, scales="free_y")