Complex sentence: For example, Sweden began compulsory recordkeeping in 1749; the data is considered accurate since 1860 (Wilmoth, 1999); prior to this, age claims in Sweden went as high as 147.
Split into simpler sentences: For example, Sweden began compulsory recordkeeping in 1749; the data is considered accurate since 1860 (Wilmoth, 1999). Prior to 1860, age claims in Sweden went as high as 147.