Dear Statalist, I want to construct the cumulative-distribution column. I tried below-two commands but results are not-correct.

HTML Code:
. bys year: gen cummat = _n * pcmat

. bys year: egen cummat1 = max(cummat)

. 
. tabdisp year, c(pcmat cummat cummat1)

----------------------------------------------
     year |      pcmat      cummat     cummat1
----------+-----------------------------------
     2003 |   .0781001    .0781001    2.343003
     2004 |   .1447923    .1447923    7.384408
     2005 |   .1610266    .1610266     7.08517
     2006 |   .3227845    .3227845    24.53162
     2007 |   .5714908    .5714908    60.57803
     2008 |   1.051938    1.051938    239.8419
     2009 |   1.352345    1.352345    408.4083
     2010 |   2.676464    2.676464     1536.29
     2011 |   2.998298    2.998298    1757.002
     2012 |   5.357974    5.357974    5550.861
     2013 |   5.217203    5.217203     6417.16
     2014 |   5.526898    5.526898    7997.421
     2015 |   8.223252    8.223252    17227.71
     2016 |   13.52689    13.52689    37550.65
     2017 |   10.69372    10.69372    35267.88
     2018 |   12.48629    12.48629    47348.01
     2019 |   13.48302    13.48302     53743.3
     2020 |   16.12752    16.12752    77412.11
----------------------------------------------

Below is my sample data:
Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input float pcmat
.0781001
.1447923
.1610266
.3227845
.5714908
1.051938
1.352345
2.676464
2.998298
5.357974
5.217203
5.526898
8.223252
13.52689
10.69372
12.48629
13.48302
16.12752 
end