st: why do I lose data, and changes my data when I create new variables and recode missing variables

[muuszls@aston.ac.uk]

why do I lose data when I create new variables and recode missing variables?

First I replace all my variables like this for example: replace turngrow=.
if turngrow==-999
(2307 real changes made, 2307 to missing)

Then I have a variable gdivs (percentage of females in companies)
When I summarize gdivs the mean is=26.98899

Variable	Obs	Mean    Std.	Dev.	Min	max

gdivs	3249	26.98899	32.9987		0	100

I want to create a variable that shows gdivs into 5 categories:

generate genderdivs    = .
(3448 missing values generated)

replace  genderdivs   = 1 if (gdivs == 0)
(3253 real changes made)

replace  genderdivs    = 2 if (gdivs > 0) & (gdivs <25)
(82 real changes made)

replace  genderdivs    = 3 if (gdivs >= 25) & (gdivs <50)
(319 real changes made)

replace  genderdivs    = 4 if (gdivs >= 50) & (gdivs <75)
(825 real changes made)

replace  genderdivs    = 5 if (gdivs >= 75) & (gdivs <.)
(344 real changes made)

When I tabulate genderdivs 5 categories are displayed:

genderdivs Freq.	Percent	Cum.

1	1,679	51.68	51.68
2	82	2.52	54.20
3	319	9.82	64.02
4	825	25.39	89.41
5	344	10.59	100.00

Total	3,249	100.00

Now when I close STATA, save it under a new name and open it again another
time the mean for gdivs changes from 26.98899 to a lower value. Sometimes
21, sometimes 10.91 (I tries it a couple of times)
And when I tabulate genderdivs 6 categories appear (a zero category is
included although I didnt command for that), instead of 5 (which I want)

What do I do wrong? Is there something wrong with how I save or open
things? Or with my commands?

Appreciate your help!


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