考虑下面提供的样本数据集;
structure(list(store_id = c(1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L,
2L, 2L, 2L, 2L, 2L, 2L, 2L), date_invoiced = structure(c(18231,
18233, 18235, 18237, 18239, 18241, 18243, 18245, 18247, 18249,
18251, 18253, 18255, 18257,