Checking previous record pages does not give any better indication of complete year. However there is a copyright date of 1938 on the form used.
I looked up the film. The records are from 1913 to 1916.
Since this is a secondary document, A Grantors Index to Deeds, can one really use the idea of a typewriter being invented in 1868 or the date of 1938 as contextual clues? This could be a indexed compilation of many years worth of records and not necessarily only those of the 20th century.
Melissa is correct. That's why I looked up the film to determine the exact years of the images on it.
Very many times we are indexing a secondary source which was typed or written many years after the original documents were created.