Korelsky, V. F. Fish, fishermen and fish industry in Russia / V. F. Korelsky. - Bremen : Krebs, [1993?]-.

For the years not adjacent in the table, the submatrix is written out separately. Let us write it, му, for 1985 and 1990: 100.0 93.90' 1990 100.0 92.51 100.1 101.50, 1985 The total number of submatrixes that have an economic sense is equal to the number of submatrixes of years adjacent in the table, i.e., to the number of columns minus unities and plus the number of submatrixes of yean not adjacent in the table (the sum of the numbers of a successively decreasing by unity row of numbers beginning with the number of columns reduced by two). Thus, if the number of columns is six, as in Table 2, the total number of submatrixes is calculated as follows: (6 -1 ) + 4 + (4 - 1) + (4 - 2) + (4 - 3) « 15. Or,still simpler 5 + 4 + 3 + 2 + 1 = 15. In another way, the total number of submatrixes is defined by the number of combinations of n columns taken AT at a time (n > K): n I ' ЛГ!(/»-*)! In our case g , 6 - S - 4 - 3 - 2 . 1 2 21 - 4 - 3 - 2 1 In the general case, we can write the submatrix of the adjacent and not adjacent years 3 x 2 in size, which we shall isolate from the general matrix 3 x 6 in size, as follows: % x2y У, r2 U z j Let us write a submatrix for 1985-1986: X2 1986 '100.0 100.0' Ух Уг = 100.0 104.0 U Z 2 J 1985 ^100.0 96.13, 8 7