Analyses of more than four decades (1979–2024) of  mean horizontal winds in the mesopause region at about 90 km  altitude show long-term trends and an influence of the 11-year solar cycle. After the 1990s, both linear trends and the solar cycle effect change and strongly weaken, indicating a change in dynamics or solar forcing. Gravity wave proxies also show a solar cycle effect, which decreases after the 1990s.