  Helioseismic data for solar cycles 23 and 24 have shown unequivocally that
solar dynamics changes with solar activity. Changes in solar structure have
been more difficult to detect. Basu & Mandel (2004) had claimed that the then
available data revealed changes in the HeII ionization zone of the Sun. The
amount of change, however, indicated the need for larger than expected changes
in the magnetic fields. Now that helioseismic data spanning two solar cycles
are available, we have redone the analysis using improved fitting techniques.
We find that there is indeed a change in the region around the HeII ionization
zone that is correlated with activity. Since the data sets now cover two solar
cycles, the time variation is easily discernible.
