This graph was plotted from the observed and expected frequencies, as given above, using these instructions to R:

plot(c(0,1,2,3,4,5), c(133,20,5,2,1,1), xlab='No. admissions / individual', ylab='frequency', main='Observed and expected frequencies') points(c(0,1,2,3,4,5), c(122.7,34.1,4.7,0.4,0,0), col='red', type='h')

Alternately, R can fit and plot the Poisson distribution using these instructions:

r=0:5 plot(r,c(133,20,5,2,1,1), xlab='No. admissions / individual', ylab='frequency', main='Observed and expected frequencies') points(r, dpois(r,0.278)*162, col='red', type='h')