We filed for the CR1 immigrant visa in early April after we returned from our honeymoon. We did not have a long history of relationship as we had met online and we married during our first meeting. The only things we had available to show at the time was a joint Tunisian bank account, wedding photos,receipts for wedding/honeymoon expenses, our joint Tunisian lease signed by landlord and validated by the local municipality office. It takes time to process the application so while it was being processed we continued to just stash away things as proof. So photos, or receipts from things we did together, etc were just kept to the side as proof to show the consulate when interview day came, though we didn't need to show them. We just showed up for the interview and they gave him the visa with hardly any questions or asking for additional proof... So no, you don't need two years of proof for the CR1, the proof we provided was from the first few weeks of marriage only and was easily approved.