/** compute mortality rates in HRS (overall and by age)

numerator = Rs who died during a year

denominator = Rs who were alive in a year: entered sample in this year or earlier and died after this year or never died

Rs who died with no death date are dropped

1. find year of first wave after entry

2. find death year

3. for those with missing death date who left sample, find last interview year

4. make person-year observations during time in HRS sample, with flag in last year for death

5. summarize

*/

set maxvar 15000

global firstwave 1
global lastwave 12

local fixvars hhidpn ranyear radyear randatef raidatef

* load RAND HRS keeping only necessary variables
use /sch-data-library/public-data/HRS/Unrestricted/RAND-HRS/rndhrs_p.dta, clear

keep `fixvars' r*iwstat r*wtresp r*iwbeg r*iwend

* find first year in sample
gen firstyr = 30000
forvalues i = $firstwave(1)$lastwave {  
	local year = 1990 + 2*`i'
	di "wave `i' year `year'"
	replace firstyr = `year' if inlist(r`i'iwstat,1,4,5) & `year' < firstyr
}

* find last year in sample
gen lastyr = 1000
gen lastwtyr = 1000
forvalues i = $lastwave(-1)$firstwave {  
	local year = 1990 + 2*`i'
	di "wave `i' year `year'"
	replace lastyr = `year' if inlist(r`i'iwstat,1,4,5) & `year' > lastyr
	replace lastwtyr = `year' if !missing(r`i'wtresp)  & `year' > lastwtyr
}

count if !missing(radyear) & lastyr + 3 < radyear

gen ttd = radyear - lastyr if !missing(radyear)
count if !missing(ttd) & ttd < -2

count if !missing(radyear) & radyear - lastwtyr >= 3


/*
* keep denominator cases
** drop Rs who haven't entered the sample or already died
drop if inlist(iwstat,0,6)

* flag numerator cases
gen died = iwstat==5 if !missing(iwstat)
label var died "died in this wave"

* carry last live weight over to death wave
sort hhidpn wave
replace wtresp = wtresp[_n-1] if died==1
bys wave: count if died==1 & missing(wtresp)


* move from waves to years
gen year = 1992 + 2*(wave - 1)
tab year
** make sure year of death falls within the years for each wave
li if died==1 & (radyear < year-1 | radyear > year)

expand 2, gen(yroffset)
replace year = year - yroffset

*/