The Total column shows the total number of people in that county or town with this surname.
For example, there were 446 people called BILLEN in Toller Porcorum at the time of the 1881 census.
The Frequency column shows the percentage of people in this county or town
with this surname. For example, a frequency of 9411.7647 in Toller Porcorum means that
9411.7647% of the people in Toller Porcorum on census day were called BILLEN.
The Index column shows the relative probability of finding someone called BILLEN
in this county or town, compared with the probability of finding them anywhere in Britain as a whole.
An index of 1 means that if you pick someone at random from this county or town, you have exactly the same
probability of picking someone called BILLEN as if you picked at random from the whole of the UK.
Where the index is higher than 1, then you are more likely to find someone called BILLEN here
than if you picked from the UK as a whole, and where it's lower then you are less likely. The actual figure
shows the level of probability - for example, a figure of 2 would indicate that you are twice as likely to find
someone called BILLEN here than in the UK as a whole, and 10 would make it ten times as likely.
The value of 0.45 in Toller Porcorum means that you are 0.45 times as likely to find
someone with the surname of BILLEN in Toller Porcorum than you would be in the whole of the UK.