I do not believe it is correct.
As time goes by, so does the inch. But, it says that only 1/4 falls, not 1 1/2. Say Y is constantly one. At hour one, it should be 1 1/4. At hour two, it should be 1 2/4 (or 1 1/2). At hour three it should be 1 3/4. At hour four, only now will it become 2 inches. They added to many in this table.
Good luck!
