Thank you for your post. However, the spelling change was not due to census takers, etc. The prior generations spelled the name Laubach, some in the next generation spelled it Laubaugh (even on tombstone), then the following generations reverted back to Laubach.
Someone suggested the spelling change may have been due to a family dispute. That could be possiible. My fathers grade school records have Laubaugh, his high school and all records going forward have Laubach. His father (Laubaugh) had died by the time my father was in high school so maybe then they reverted to the older spelling (Laubach).