"The changing dominance and outperformance by a few sectors such as consumer staples, consumer discretionary, private sector financials and export-oriented sectors such as IT and pharma in the CNX Nifty is driving the index to January 2008 levels," the rating agency said.
The CNX Nifty closed at 5,742.30 on Wednesday. The country's gross domestic product growth fell from sub-9 per cent in FY08 to a decade-low of 5 per cent in the fiscal year ended March 31.
The index does not reflect the current state of the economy and convey the worsening macro-economic situation, the report said.
Consumption and export-oriented sectors now command a 65 per cent weightage on the Nifty compared with 29 per cent in 2008 due to strong financial performance and increase in valuation over the past five years, it said.
In this period, the aggregate PAT of the companies in these sectors has grown at a CAGR of 21.9 per cent, Crisil said.
According to Crisil, the weightage of any company or sector in the index is determined by the relative free-float market capitalisation of the constituents.
In January 2008, investment-linked sectors such as materials, industrials, energy, utilities and telecom dominated the index with a weightage of 66 per cent.
However, the current economic downturn has resulted in poor performance of these sectors, it added.
"The aggregate earnings of companies in investment-linked sectors remained almost flat during the period," the Crisil report said.
Consumer-oriented sectors and private sector financials have benefited from the consumption boom and government policies, while IT and pharma have received support from recovery in the global economy and a weakening domestic currency, it said.
Among the biggest gainers of the pack are Lupin (599 per cent) and Sun Pharma (372 per cent).
The report further stated that while the consumption and export-linked sectors have provided resilience to the Nifty, policy impetus towards investment-linked sectors is now critical for any sustainable uptick to the markets at large.