To some extent, it may be explained by increasing productivity, international competition, outsourcing, and generally falling manufacturing costs. It's not the complete story, however.
The rest of it: major changes in the CPI methodology. Particularly the last line (discontinued the asset-price approach) has made a big difference. Inflation has never been the real thing since then.
The real inflation (with property prices) was rather high from 2000 to 2006. Yet the Fed ignored the inflation threat as it has used the official (rigged) CPI definition.