Stata Data Formats
The Stata data file format encodes variable metadata including display formats. While these formats primarily affect visualization, they can also encode critical information about how a variable should be used.
See also the underlying data types.
Contents
Display Formats
A display format is set like:
generate double my_datetime = clock(some_string, "YMDhms") format my_datetime %tc
Numeric Formats
For the most part, all numeric types operate the same way in Stata.
See Numeric Functions for operating on this type of data.
Each underlying numeric data format applies a different display format by default. They are:
Type |
Format |
double |
%10.0g |
float |
%9.0g |
long |
%12.0g |
int |
%8.0g |
byte |
%8.0g |
The available numeric formats are:
general format (g) indicating that the number of decimal places should be shifted to improve readability
fixed width format (f) indicating that a fixed number of decimal places should be shown
scientific format (e) indicating that scientific notation should be used
As an example:
Value |
With format %9.4g |
With format %9.4f |
With format %9.2e |
3.14159 |
3.142 |
3.14 |
3.14e+00 |
314.159 |
314.2 |
314.16 |
3.14e+02 |
A c can be appended to any numeric format to display commas.
Date and Datetime Formats
Dates and datetimes are numeric data with a standardized, encoded meaning. The display format is what indicates the intended encoding. For the most part, this type of data counts days or milliseconds from the Stata epoch: 01jan1960 00:00:00.000.
See Datetime Functions for operating on this type of data.
Specifically, the date and datetime formats are:
Format |
Unit |
%tc |
milliseconds ignoring leap seconds |
%tC |
milliseconds with leap seconds |
%td |
days |
%tw |
weeks |
%tm |
months |
%tq |
quarters |
%th |
half-years |
%ty |
years |
These formats can be further customized, for visualization purposes only, with specific components.
Component |
Specification |
Displays As |
Century |
CC |
01-99 |
Century |
cc |
1-99 |
Year |
YY |
01-99 |
Year |
yy |
1-99 |
Day of year |
JJJ |
001-366 |
Day of year |
jjj |
1-366 |
Month |
Mon |
Jan-Dec |
Month |
Month |
January-December |
Month |
mon |
jan-dec |
Month |
month |
january-december |
Month |
NN |
01-12 |
Month |
nn |
1-12 |
Day |
DD |
01-31 |
Day |
dd |
1-31 |
Day of week |
DAYNAME |
Sunday-Saturday (aligned) |
Day of week |
Dayname |
Sunday-Saturday (unaligned) |
Day of week |
Day |
Sun-Sat |
Day of week |
Da |
Su-Sa |
Day of week |
day |
sun-sat |
Day of week |
da |
su-sa |
Half-year |
h |
1 or 2 |
Quarter |
q |
1-4 |
Week |
WW |
01-52 |
Week |
ww |
1-52 |
Hour |
HH |
00-23 |
Hour |
Hh |
00-12 |
Hour |
hH |
0-23 |
Hour |
hh |
0-12 |
Minute |
MM |
00-59 |
Minute |
mm |
0-59 |
Second |
SS |
00-60 (due to leap second) |
Second |
ss |
0-60 (due to leap second) |
Tenths |
.s |
.0-.9 |
Hundredths |
.ss |
.00-.99 |
Thousandths |
.sss |
.000-.999 |
AM/PM |
am/pm |
am or pm |
AM/PM |
a.m./p.m. |
a.m. or p.m. |
AM/PM |
AM/PM |
AM or PM |
AM/PM |
A.M./P.M. |
A.M. or P.M. |
Period |
. |
. |
Comma |
, |
, |
Colon |
: |
: |
Hyphen |
- |
- |
Space |
|
|
Forward slash |
/ |
/ |
Back slash |
\ |
\ |
Literal character |
!c |
c |
A plus sign (+) can optionally delimit components for human readability. It is ignored otherwise.
String Formats
Alignment is controlled by the presence or absence of a negative sign (-) ahead of the width. A string variable formatted as %-18s will be left-justified; with a format of %18s it would have been right-justified.