BSE 100

About S&P BSE 100 Today

The S&P BSE 100 stock index is designed to provide market performance gauging for the top 100 most liquid companies listed on the BSE. Stocks that are constituents of this index come in either the mid-cap or large-cap categories or their values have been float-adjusted. Thus, the index value changes with ups and downs in the prices of BSE 100 shares.

In other words, the index only includes the actively traded shares in the market and excludes the closely held shares. Companies in the list for BSE 100 are reviewed and updated twice a year in June and December. Several criteria are considered for selecting the top 100 stocks in the S&P BSE 100 index. 

The BSE also computes a dollar-denominated version of the BSE SENSEX 100, called the Dollex-100. This index represents the value of the BSE 100 in US dollars.

History of BSE 100

The BSE 100 index, which started originally under the name BSE National Index in 1989, was later rebranded as the S&P BSE 100 index in 1999. Presently, it includes about two-thirds of the aggregate market capitalization of all the stocks traded in BSE. Thus, this index happens to be an indicator of the performance of major, highly liquid companies on the BSE and accounts for a sizeable chunk of its overall market value. The wide representation of this index makes it one of the most critical gauges of the trend in the Indian broader market and economy as a whole.

Criteria to Select Stocks for Inclusion in BSE 100

Here are the criteria to select stocks for inclusion in the BSE 100: 

• Listing Requirements: Stocks must have been listed for at least 3 months.
• Market Capitalization: The company should be large-cap or small-cap.
• Liquidity: The companies' stocks shall be highly liquid, traded at least on 95% of the trading days in the last 3 months.
• Sources of Income: The income should be generated mainly from the core operation of the business.
• Trading Volume: The annual traded value of the firms must be more than 10 million.

Calculation of S&P BSE 100

The index, earlier calculated under the full market capitalization method that considered both actively traded and closely held shares, was replaced in 2003 by the float-adjusted market capitalization approach. In this approach, only those shares that are free to float in the market are considered for calculating market capitalization. 

Here's how it has been revised: 

Step 1: The market capitalization of a company is determined by multiplying the total number of shares by the market price or the BSE 100 share price.

Step 2: Calculate the percentage of free-floating shares that are available to the market for trading.

Step 3: Multiply this percentage of the free-floating shares with the market capitalization determined in Step 1, which gives the float-adjusted market capitalization. 

The formula is: 

BSE 100 Today = Total Free - Float Market capitalisation x 100