Q5. How many observations does the dataset have? A4. 6000

. 
end of do-file

. cd /users/d/desktopo
unable to change to /users/d/desktopo
r(170);

. cd /users/d/desktop
/Users/d/Desktop

. do "/Users/d/Desktop/twoway.do"

. 
. 
. foreach command in quietly noisily {
  2. 
.     `command' {
  3.     
.               if 1 { //log,set,macro
  4.         
.                   timer on 1
  5.         
.                   capture log close
  6.                   log using wk1.ph.340.700-`command'.log, replace 
  7.         
.                   cls 
  8.         
.                   global url https://data.nber.org/mortality/
  9.                   global filename mort1959.dta
 10.         
.                   timer off 1
 11.         
.               }
 12.     
.               if 2 { //timer,loop,data
 13.         
.                   timer on 2
 14.         
.                   forvalues i=1959/1961 {
 15.             
.                       use "${url}`i'/mort`i'", clear 
 16.                       save y`i', replace 
 17.             
.                   timer off 2
 18. 
.                   }
 19.         
.         
.         
.               }
 20.     
.               if 3 { //clear,append,save
 21.     
.                   timer on 3
 22.         
.                   clear 
 23.                   forvalues i=1959/1961 {
 24.             
.                       append using y`i'
 25.             
.                   }
 26.          
.                   save mort.usa, replace 
 27.         
.                   timer off 3
 28.         
.               }
 29.     
.               if 4 {
 30.         
.                   timer on 4
 31.         
.                   noi di "# of deaths: `c(N)' & # of variables: `c(k)'"
 32.                   noi lookfor year
 33.                   g deaths=1
 34.                   
.                   preserve 
 35.                   collapse (count) deaths, by(datayear)
 36.                      noi di "# of deaths: `c(N)' & # of variables: `c(k)'"
 37.                      noi list 
 38.                      #delimit ;
delimiter now ;
.                      line deaths datayear, 
>                        sort 
>                         ti("United States")
>                         xti("Year");
 39.                       #delimit cr
delimiter now cr
.                   restore
 40.         
.                   noi di "# of deaths: `c(N)' & # of variables: `c(k)'"
 41.                   timer off 4
 42.         
.               }
 43.     
.               if 5 {
 44.         
.         
.                   save mort.fig, replace 
 45.         
.                     
.               }
 46.     
.     timer list 
 47.     log close 
 48.     
.     }
 49.     
. }