The authors of this report aim to understand the health of the science, technology, engineering, and mathematics (STEM) education and labor market in the Appalachia region -- defined as the intersection of Ohio, Pennsylvania, and West Virginia -- with a focus on the mining and extraction industry. This report is the third in a three-part series. The first two reports provided initial examinations of STEM education and the labor market in the Appalachia Partnership Initiative (API) region. In this report, the authors address the same questions as the first two reports but devote more attention to examining whether and how any of the indicators have changed over time. The authors also tighten the analysis specifically to the API region and introduces a few new measures, such as participation in career and technical education (CTE). Key Findings: (1) Middle school students in the API states have outperformed students nationwide in mathematics, and trends are improving over time; (2) CTE in the API region has room for growth; (3) High school graduation rates are high and improving; (4) Although postsecondary enrollment decreased in the API region over time, the percentage of students graduating in STEM has been increasing and outstripping the national average; (5) The working-age population declined within the API region; (6) Median earnings were higher in suburban areas of the API region and lowest in parts of the urban centers, but there was no clear geographic pattern of growth in median earnings; (7) Earnings were high and growing in the mining and utilities industry in the API region; (8) The mining and extraction industry was particularly successful at compensating workers who held a high school degrees or had less education; and (9) New hires from outside the extraction industry in API states primarily came from within the region but from other industries and enjoyed large earnings increases. [The research was conducted with the RAND Social and Economic Well-Being Division. For "Wages, Employment, and STEM Education in Ohio, Pennsylvania, and West Virginia. Report No. 1 (2016). Research Report. RR-1357-CHC," see ED605413. For "Wages, Employment, and STEM Education in Ohio, Pennsylvania, and West Virginia. Report No. 2 (2017). Research Report. RR-1863-CHC," see ED605433.]