<prompt> Translate the following text to EnglishKama ilivyoelezwa hapo juu, matarajio ya busara ni changamoto kwa uchumi wa Keynesian, ambayo haikuunda muundo mpya wa kazi kwa nadharia ya uchumi wa jumla na sera, lakini iliharibu sana muundo wa zamani.  <response>: You see, the rational expectations challenge to Keynesian economics was half- It did not build a workable new structure for macroeconomic theory and policy, but it did seriously damage the old structure. 