**1. Introduction**

The labor markets for health care workers are important to monitor and evaluate, as these workers are still the driving force behind the delivery of goods and services that improve the health of individuals and entire populations. This is particularly important in the profession of pharmacy, where the increased reliance on medications as a form of treatment requires trained personnel to ensure that medications deliver desired outcomes and avoid undesired outcomes.

Some degree of attention has been paid over the years to the labor markets for health care professionals, such as those for physicians, pharmacists, nurses and others who are educated and trained to play specific roles in serving our health needs [1–3]. As health care has become more specialized and complex, health professionals have increasingly relied on para-professional workers to support their clinical roles and provide administrative assistance. In pharmacy, the role of the pharmacist has been increasingly supported by the pharmacy technician. Pharmacy technicians support pharmacists in dispensing medications, performing clinical functions needed to improve the outcomes of mediation use [4–6], and to perform a number of administrative functions which assist in the operations of a pharmacy [7]. Pharmacy technicians have been asked to increasingly take on roles that had previously been exclusively performed by pharmacists, including reviewing medications and checking the work of other technicians prior to dispensing [8,9], taking medication histories [10], managing warfarin therapy within a clinical pharmacy anticoagulation service [11] and immunization delivery [12]. Pharmacists depend upon a stable labor market of pharmacy technicians to support them in optimizing patient health outcomes. The ability to delegate and empower others is demonstrative of a pharmacist practicing at the top of their license [13].

The number of pharmacy technicians working in the United States has grown from 165,400 in 1997 to 420,400 in 2018 [14]. The number of pharmacy technicians in the US now surpasses the number of pharmacists (314,300). The United States Bureau of Labor Statistics (US BLS) projects that the job market for pharmacy technicians will grow by 7% between 2018–2028, adding 31,500 positions [15]. At the same time that the US BLS is not projecting any net growth in the number of pharmacist positions needed in the US [16].

The supply and demand of health care professionals has been the subject of considerable research. The labor market for pharmacists in the United States has been evaluated by means of the aggregate demand index (ADI) [17], and later by the pharmacist demand indicator (PDI) [18]. Pharmacist demographics, working conditions and other trends in pharmacist practice in the US are examined in the National Pharmacist Workforce Survey, which has been conducted every five years since 2000 [19]. Our understanding of the supply and demand of pharmacy technicians in the US and their working conditions are more limited. Desselle and Holmes conducted a National Certified Pharmacy Technician Workforce Survey in 2015 which described various aspects of their working conditions, including a finding that over one in four certified pharmacy technicians (26.6%) were "highly dissatisfied" with their wages [20]. Urick and colleagues noted that while many US states adopted additional barriers to entry to working as a pharmacy technician between 1997 and 2017, such as registration with a state entity and national certification requirements, these barriers were not associated with any changes in pharmacy technician wages [21]. Mattingly and Mattingly also found that that were no significant di fferences in pharmacy technician wages in 2016 based on the degree of regulation of pharmacy technician practice in that state or the cost of living in a state as measured by the salary housing index [22]. Mattingly and Mattingly also concluded in their systematic review of literature regarding the roles of pharmacy technicians that while evidence supports technicians performing roles which advance pharmacy practice and improve patient outcomes, the benefits to technicians in performing these roles have been limited to increases in their job satisfaction and work schedules, and not in their levels of wages or other forms of financial compensation [23]. They further concluded that if pharmacy technicians are to take on more roles in the future, they may need to be offered more tangible forms of benefits, particularly if these roles require completion of formalized education and training programs.

Limitations of much of the previous research on pharmacy technician labor is that it is cross sectional and only describes labor market conditions at a particular point in time. Little research has been done to evaluate how pharmacy technician wages have changed over time, and how that in turn this has been reflected by changes in the number of technicians leaving or entering the labor market. Even more scarce is research evaluating trends in various sectors of the labor market for pharmacy technicians, sectors which can be defined by the setting in which the work takes place (e.g., chain and independent pharmacies, grocery store pharmacies, mass merchandise store pharmacies, hospitals, governmen<sup>t</sup> agencies).

Since 1997, the US BLS has collected data annually on over 800 occupational groups, including pharmacists and pharmacy technicians. Among the data collected by the BLS for each occupational group are the mean and median annual salary and hourly wage levels, as well as the number employed in that group. US BLS occupational group data can be further analyzed by workplace setting. The objective of this research is to use US BLS data to evaluate changes in pharmacy technician wages in the United States from 1997 to 2018 relative to changes in the US consumer price index (CPI) over that time. The underlying hypothesis for this comparison is that if the supply and demand for labor are in balance, changes in wages for that occupation will match changes in the CPI. If di fferences between an occupation's wages from what would be predicted by changes in CPI are noted, that would be a signal that the supply and demand are not in balance. For example, increases in real wages over those predicted by CPI could be explained by both shortages of labor, and/or increased demand for that service. Decreases in real wages relative to CPI may be indicative of just the opposite; a combination of oversupplies of labor in that market and/or decreased demand for that particular type of labor.
