The FLRW metric is used to model our Universe on large cosmological scale. It is a conformally flat metric and the form of stress energy tensor that we get from Einstein's equations are often equated to stress energy tensor for an ideal fluid. This ideal fluid is interpreted to describe a combination of matter fields (dust) and radiations. Now, it is generally the case that any local source of energy and matter distribution would produce a non-zero conformal curvature. So is it really justified to interpret stress energy tensor in FLRW cosmology to represent a general matter-energy distribution (dust + radiation)? This model has predicted that percentage of ordinary matter is only 4%, dark matter 24% and dark energy 72%. Should we need to revisit these claims if interpretation of stress energy tensor is inaccurate?