def div_growth_rate(t, dt, d0):
	"""
	Calculates the growth rate of a dividend using the dividend growth rate
	valuation model.
	
	parameters:
	-----------
	t = time
	dt = current price of dividend
	d0 = price of dividend t years ago

	"""
	growth_rate = (((dt/d0) ** (1/t)) - 1) * 100
	return round(growth_rate, 4)