I'm not querying the math - see first para. -  but saying that how/when/where it is applied may be a political choice or based on available funding.  Neither am I dismissing the modernisation theory entirely - it is a model that can be applied - just saying that it is not the only, or necessarilly the "best" theory, but that it is very congruent with the dominant western conceptions of development and underdevelopment.

notes from no w here