Other implementation of Hui's formula include = LN(3500/2766) / LN(1.04) [mathematically preferred solution]
and = LOG(3500/2766, 10) / LOG(1.04, 10)[pre-computer era 'sums']

Out of curiosity, why does the example calculation result in a value so close to the integer 6?
Does the calculation represent 6 years growth, say?