Genesis 41:27-31

The seven ugly and scrawny cows that followed and the seven shriveled ears scorched by the east wind are seven years also. They represent seven years of famine. It is just as I have told Pharaoh; God has divinely revealed what he is about to do. There will come seven years of great abundance throughout all the land of Egypt, followed by seven years of intense famine. All of Egypt will forget the former abundance, for all the land will be ravaged by a famine, a very severe famine. They will not even remember their former abundance.