Rahrs in the census Returns
There are census returns available for various dates between 1787 and 1916:
1787, 1. July
1801, 1. February
1834, 18. February
1840, 1. February
1845, 1. February
1850, 1. February
1855, 1. February
1860, 1. February
1870, 1. February
1880, 1. February
1890, 1. February
1901, 1. February
1906, 1. February
1911, 1. February
1916, 1. February
There is a useful page about the Danish census returns at: http://www.rootsweb.com/~dnkcen/danish_census_faq.html
Click on the relevant district in the left menu