If unverified and additional reports from previous years are included, for the 40 years can be attributed to any other estimate of 5 to 6 thousand more years.
Kama taarifa zisizokuwa na ushahidi na zaidi kutoka miaka ya nyuma ni pamoja na, kwa miaka 40 unaweza kuhusishwa na makadirio nyingine yoyote ya miaka 5-6000 zaidi.