Joseph said that there would be seven years of plenty, and then seven years of famine.
This is talking about food production. Seven good years, ie years of plenty and seven bad years ie years of famine.
Joseph interpreted Pharaoh's dream of seven lean cows eating seven fat cows as a prediction of seven years of plenty followed by seven years of famine in Egypt. He advised Pharaoh to store up grain during the years of plenty to prepare for the coming famine.
The dream of the cows indicated that Egypt would have seven years of abundance followed by seven years of famine.
The seven fat cows referred to seven years of abundant harvest and the seven lean cows referred to seven years of famine.
(Genesis ch.41) That there would be seven years of plenty, followed by famine.
According to Genesis 41, the chief butler told Pharaoh about Joseph's remarkable ability to accurately interpret dreams. See verses 8-14.
Of course, storing up food for seven years in preparation for the biblical seven year famine would be a logistics exercise of unprecedented proportions. But it seems that it never happned. The Egyptians kept detailed documents of all the minituae of life, including contracts and business dealings, but scholars have never been able to find a reference to any such famine. Food was not stored during the famine, because it never really happened.
Joseph informed Pharaoh that there would be seven years of great bounty in Egypt, followed by seven years of famine (Genesis ch.41). See also:More about Joseph
The potato famine, in the second half of the 1840s.
For Five years
368 years