Why did the Assessing Department leave a door hanger at my property?

The following letters written on the door hanger explain the reason
for the Assessing Department's visit to your property.
C = Correction - Recently discovered evidence indicates that the information we have pertaining to your property may need to be corrected.
F = Follow-Up - We are following up on a prior visit to ascertain the current state of changes that were started on the property.
H = HomeOwner Request - We are responding to your request to ascertain the accuracy of our assessment of your property.
P = Permit - A building permit was issued for your property within the past year.
R = Cyclical Review – The Department visits all properties in the city on a revolving basis to verify that the physical attributes of the properties match our records.
S = Sale -  Questions resulting from a recent sale.