_dta:
  1.  usint set up by Jean Roth , jroth@nber.org , 18 Oct 2016
  2.  Source URL: http://www.census.gov/popest/data/intercensal/national/index.html
  3.  File Layout: http://www.census.gov/popest/data/intercensal/national/files/US_INT90.txt
  4.  Source File: http://www.census.gov/popest/data/intercensal/national/files/US-EST90INT-07.csv

dateest:
  1.  Date of Population Estimate

agestr:
  1.  AGE - All ages and single-year of age (0, 1 ,2, ... 100+ years

pop:
  1.  Population

popmale:
  1.  Population - Males

popfemale:
  1.  Population - Females

age:
  1.  AGE - All ages and single-year of age (0, 1 ,2, ... 100+ years

year:
  1.  Year

yearest:
  1.  Calendar Year of Estimate

monthest:
  1.  Calendar Month of Estimate

  obs:        12,342                          
 vars:             9                          18 Oct 2016 14:02
 size:       518,364                          (_dta has notes)
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              storage   display    value
variable name   type    format     label      variable label
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dateest         str17   %17s                * Date of Population Estimate
agestr          str7    %9s                 * AGE - All ages and single-year of age (0, 1 ,2, ... 100+ years
pop             long    %12.0g              * Population
popmale         long    %12.0g              * Population - Males
popfemale       long    %12.0g              * Population - Females
age             byte    %10.0g     age      * AGE - All ages and single-year of age (0, 1 ,2, ... 100+ years
year            int     %9.0g               * Year
yearest         int     %9.0g               * Calendar Year of Estimate
monthest        byte    %9.0g               * Calendar Month of Estimate
                                            * indicated variables have notes
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Sorted by: year  yearest  monthest  age