Equal-weight index: For diversified investments with low volatility

• Equal-weight indices give equal weightage to all the stocks making up a benchmark.
  
  
• On an equal-weight index, no stock can unduly influence the index movement and all stocks get almost the same representation – making for a fairly well-diversified portfolio.
  
  
• When many of the market constituents witness strong rise in stock prices, an equal-weight index can deliver better returns than a concentrated portfolio.
  
  
• In an equal-weight index, as a result of the same weightages to all stocks, the level of sector concentration also becomes reduced.

Many retail investors would be familiar with regular index investing. This often entails investing in funds that track indices such as the Nifty 50 and the Nifty 100. The stocks that form a part of these indices are given weightages based on free float market capitalisation – we’ll come to it in a bit. Therefore, each stock has a different weightage in the overall index.

An interesting variant that has been gaining traction is equal-weight index investing. So, these are indices that accord equal weights to stocks. Here’s more on what goes into equal-weight indices and what you must understand before investing in them.

How free-float and equal-weight indices vary

As mentioned earlier, the regular Nifty 50 and Nifty 100 indices are based on free-float market capitalisation. Now, there are broadly two categories of shareholders in listed companies. Promoter and promoter groups, and trusts backed by them are one category. Public shareholders form the second type. So, the shares of promoters are not traded actively or are allowed only with many restrictions. The rest of the shares are free float and allowed to be traded in the markets. Now, the free float shares multiplied by the share price gives the free float market capitalisation. While constructing the index, the stocks with higher free-float market capitalisation get higher weightages than those with lower numbers.

Equal-weight indices, on the other hand, do away with such restrictions based on free- float market capitalization. These indices give equal weightage to all the stocks making up a benchmark. For example, all stocks get around 2% weightage in the Nifty 50 Equal weight index. In the Nifty 100 Equal Weight index, all stocks are given a weightage of around 1%.

Broad-based stock and sector representation

Investing in an equal-weight index has its fair share of advantages. Here are a few of those.

Truly well-diversified portfolio with same weightages: Let us take the Nifty 50 as an example. The top 10 stocks in the Nifty 50 account for nearly 58% of the portfolio. A few stocks can have a disproportionate impact on the movement of the index.

In the Nifty 50 Equal Weight index, on the other hand, the top 10 stocks make up only a little over 20% of the portfolio. No stock can unduly influence the index movement and all stocks get almost the same representation, thus making for a fairly well-diversified portfolio.

Chances of outperforming in broader market rallies higher: When many of the market constituents start rallying and witness strong rise in stock prices, an equal-weight index can deliver better returns than a concentrated portfolio. In the rally after the Covid-19 crash in March 2020, stocks across segments rallied. Such moves help equal-weight indices as most stocks get to participate in the rally.

And in a falling market, they may cushion downsides better as weightage to individual stocks is low (just 2% in the case of Nifty 50 Equal Weight index). In effect, the movements on the upside and downside are tempered.

In a narrower market rally led by very few stocks, a free-float market capitalization index may perform better. An example would be the markets in 2018-19.

Lower sectoral concentration: In the equal-weight index, as a result of the same weightages to all stocks, the level of sector concentration also becomes reduced. For example, the financial services sector gets 34.56% weightage in the Nifty 100 index. But in the Nifty Equal Weight index, the financial services segment constitutes only 22.05%.

Therefore, there is a better spread of exposure across sectors and a reduction in concentration in select sectors. This diffusion reduces the risks associated with the portfolio. Also, some sectors such as automobiles get better representation in the equal-weight index than the free-float one.

As a natural profit-booking index: In an equal-weight index, the rebalancing of constituents happens once every six months. Therefore, even if any stock rallies heavily during a period, its weightage would be restricted to the original equal-weight index levels. This is akin to taking profits periodically in a systematic way.

For a retail investor, the optimal way to invest in an equal-weight index is through an index fund that tracks and replicates, say, the Nifty 50 equal weight index. Such an offering could be a diversifier to the portfolio. To further understand product suitability, it is best to seek help from a financial advisor before investing.

(The author is the Head Investment Strategy at ICICI Prudential Asset Management Company)