On wedding invitations, etiquette authorities agree, the year is traditionally written as text. It is for this reason, I suppose, that some authorities think to address capitalization of the year. However, there is no consensus. It is more common to see the advice to capitalize the first word of the year (only). Most Google search results for [ capitalize year wedding etiquette ] give this advice.
Mesa County, Colorado (CO) County population in 2014: 148,255 (87% urban, 13% rural); it was 116,255 in 2000. County owner-occupied with a mortgage or a loan houses and condos in 2010: 29,788. County owner-occupied free and clear houses and condos in 2010: 11,718. County owner-occupied houses and condos in 2000: 33,306.
With 314,638 people, Douglas County is the 7th most populated county in the state of Colorado out of 64 counties. But watch out, Douglas County, because Boulder County with 313,333 people and Weld County with 277,670 people are right behind you.