Hi,

I would like to calculate the standard deviation of annual changes in log-sales over the recent five years (on a rolling five-year basis). I already calculated the annual changes in log-sales (see variable: SALE_change_log). My dataset looks like this:

Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input str24 gvkey double(fyear sale) float(SALE_change SALE_change_log)
"001013" 2010   1156.6          .          .
"001094" 2016  558.524          .          .
"001094" 2017  638.318   79.79401  4.3794484
"001094" 2018  711.359   73.04101   4.291021
"001161" 2010     6494          .          .
"001161" 2011     6568         74   4.304065
"001161" 2012     5422      -1146          .
"001161" 2016     4272      -1150          .
"001161" 2017     5329       1057    6.96319
"001161" 2018     6475       1146   7.044033
"001173" 2010   29.618          .          .
"001173" 2011   29.607 -.01100003          .
"001173" 2012   31.021  1.4139997   .3464223
"001210" 2010   83.362          .          .
"001210" 2011   89.383      6.021  1.7952534
"001210" 2012  103.064  13.680997   2.616008
"001210" 2013  100.772  -2.292003          .
"001210" 2014  112.181  11.408997   2.434402
"001210" 2015  148.212  36.031002    3.58438
"001210" 2016  148.472   .2599944 -1.3470953
"001210" 2017  194.519     46.047  3.8296626
"001210" 2018  249.834     55.315  4.0130444
"001234" 2010  108.569          .          .
"001234" 2011  117.704      9.135  2.2121131
"001239" 2010 1598.464          .          .
"001266" 2010   79.792          .          .
"001266" 2011   98.592       18.8   2.933857
"001266" 2012  127.187     28.595   3.353232
"001266" 2013  101.661    -25.526          .
"001266" 2014    88.68 -12.981003          .
"001266" 2015  153.119     64.439   4.165719
"001266" 2016  144.196  -8.923003          .
"001266" 2017  129.829    -14.367          .
"001266" 2018   81.281    -48.548          .
"001266" 2019  122.251      40.97    3.71284
"001308" 2010  659.665          .          .
"001327" 2018     3868          .          .
"001327" 2019   3376.8     -491.2          .
"001439" 2010  104.836          .          .
"001439" 2011  154.917     50.081   3.913642
"001468" 2010 1592.568          .          .
"001468" 2011 1695.144    102.576   4.630604
"001468" 2012  1872.72  177.57596   5.179399
"001491" 2010    315.9          .          .
"001491" 2011  530.476    214.576   5.368664
"001491" 2013  523.957  -6.519013          .
"001554" 2015  102.987          .          .
"001562" 2010   85.589          .          .
"001562" 2011  102.636  17.047003  2.8359745
"001562" 2012  100.467 -2.1690016          .
"001562" 2013  100.601  .13399713 -2.0099368
"001562" 2014  102.873   2.272002   .8206614
"001562" 2015  113.889     11.016   2.399349
"001562" 2016  106.286     -7.603          .
"001562" 2017  112.703   6.416997  1.8589503
"001562" 2018  108.706  -3.997003          .
"001585" 2010   229.62          .          .
"001585" 2011  304.429  74.809006   4.314938
"001585" 2012   366.19   61.76101  4.1232724
"001602" 2010    15053          .          .
"001602" 2011    15582        529   6.270988
"001602" 2012    17265       1683   7.428333
"001602" 2013    18676       1411   7.252054
"001602" 2014    20063       1387   7.234899
"001602" 2015    21662       1599   7.377134
"001602" 2016    22991       1329   7.192182
"001602" 2017    22849       -142          .
"001602" 2018    23747        898    6.80017
"001602" 2019    23362       -385          .
"001632" 2017 5107.503          .          .
"001632" 2019 5991.065   883.5621   6.783962
"001633" 2010  423.597          .          .
"001633" 2011  473.595   49.99802   3.911983
"001633" 2012  516.571     42.976   3.760642
"001633" 2013  550.363  33.792015  3.5202246
"001633" 2014  517.548 -32.814976          .
"001633" 2015  540.291  22.743027  3.1242585
"001633" 2016  508.848 -31.443016          .
"001633" 2017  486.372  -22.47599          .
"001634" 2010  106.688          .          .
"001634" 2011  109.118  2.4299965   .8878898
"001634" 2012   105.79  -3.327996          .
"001635" 2010  168.789          .          .
"001635" 2011   179.17     10.381   2.339977
"001635" 2012  147.346    -31.824          .
"001635" 2013  158.374  11.028007   2.400438
"001659" 2010 3393.791          .          .
"001659" 2011 4576.331    1182.54    7.07542
"001659" 2012  5272.01    695.679   6.544888
"001659" 2013 5604.574   332.5642   5.806833
"001661" 2010 4174.635          .          .
"001661" 2011 6060.351  1885.7162   7.542063
"001661" 2015 3864.437  -2195.914          .
"001661" 2016 2227.839  -1636.598          .
"001661" 2017 2564.285   336.4459   5.818438
"001661" 2018 3057.619   493.3341   6.201187
"001661" 2019 3043.383 -14.235896          .
"001678" 2010    12183          .          .
"001678" 2011    16810       4627   8.439664
"001678" 2012    16947        137   4.919981
end
Can anyone help me? Thanks in advance!

Roy