obs     anio   trimestre   gasto     stock
        1      1952         1     214.6     159.3
        2      1952         2     217.7     161.2
        3      1952         3     219.6     162.8
        4      1952         4     227.2     164.6
        5      1953         1     230.9     165.9
        6      1953         2     233.3     167.9
        7      1953         3     234.1     168.3
        8      1953         4     232.3     169.7
        9      1954         1     233.7     170.5
       10      1954         2     236.5     171.6
       11      1954         3     238.7     173.9
       12      1954         4     243.2     176.1
       13      1955         1     249.4       178
       14      1955         2     254.3     179.1
       15      1955         3     260.9     180.2
       16      1955         4     263.3     181.2
       17      1956         1     265.6     181.6
       18      1956         2     268.2     182.5
       19      1956         3     270.4     183.3
       20      1956         4     275.6     184.3