11 Association of Research Libraries Research Library Issues 295 — 2018 Another approach is necessary to estimate the number of individuals from the 2015 population aged 65+ who will leave the population by 2020. To calculate this estimate, I subtracted the percentage of individuals 70 and older who might remain in the population (1.5%) from the percentage in the 2015 65+ cohort (9.3%). This reduces the percentage of the 2015 population aged 65+ that can be expected to leave by 2020 to 7.8%, the equivalent of approximately 790 vacancies. Combining these two estimates, 689 vacancies from the 60–64 cohort and 790 from the 65+ cohort, yields a total of 1,479 for the period. Table 1 applies this methodology to previous years, and illustrates the dramatic uptick in departures possible in the current five-year period. Population size in prior year 60–64 departures 65+ departures Total departures 1986 to 1990 8,168 278 90 368 1990 to 1994 8,792 308 114 422 1994 to 2000 8,634 203 104 307 2000 to 2005 8,882 315 133 449 2005 to 2010 9,655 492 106 599 2010 to 2015 10,037 738 361 1,099 2015 to 2020 10,131 689 790 1,479 Table 1: Estimated Departures from the Two Oldest Age Cohorts of ARL Professionals, 1986 to 2020 Youth Movement Starts Now? The delayed retirements of 2015 have almost certainly played a role in the muted hiring levels among ARL libraries in recent years, a topic I will address in a future chapter of my analysis. It is hard to see, however, how hiring could remain low. More likely, the peak vacancies we expected between 2010 and 2015 are actually happening right now, resulting in the best market for research library job seekers in memory. The youth movement is almost certainly already in progress, but for ARL libraries, youth is not what it once was. New professionals are naturally the youngest subgroup in the population, and it is true that library schools continue to attract primarily young students, about 70% under the age of 35 in 2015.12 But ARL libraries tend to recruit