The selective service card says that he was in the USA in 1967...almost 1968.
At the time of his birth, Cruz's parents had lived in Calgary for three years and were working in the oil business as owners of a seismic-data processing firm for oil
Breitbart:
The Cruz campaign offered the following statement exclusively to Breitbart News, presented in full (original emphasis): Eleanor was never a citizen of Canada, and she could not have been under the facts or the law. In short, she did not live in Canada long enough to be a Canadian citizen by the time Cruz was born in 1970: Canadian law required 5 years of permanent residence, and she moved to Canada in December 1967—only 3 years before Senator Cruz’s birth. Nothing in the document you sent shows anything to the contrary.