How the sensex is calculated and added/deducted on a daily basis?

Question

Eg;- If the index of bse (sensex) is 10,000, how it is changing to 12000.. How the basic calculation is done?

Answer 1

How is SENSEX calculated? SENSEX is calculated using a "Market Capitalization-Weighted" methodology. As per this methodology, the level of index at any point of time reflects the total market value of 30 component stocks relative to a base period. (The market capitalization of a company is determined by multiplying the price of its stock by the number of shares issued by the company). An index of a set of a combined variables (such as price and number of shares) is commonly referred as a 'Composite Index' by statisticians. A single indexed number is used to represent the results of this calculation in order to make the value easier to work with and track over time. It is much easier to graph a chart based on indexed values than one based on actual values.

The base period of SENSEX is 1978-79. The actual total market value of the stocks in the Index during the base period has been set equal to an indexed value of 100. This is often indicated by the notation 1978-79=100. The formula used to calculate the Index is fairly straightforward. However, the calculation of the adjustments to the Index (commonly called Index maintenance) is more complex.

The calculation of SENSEX involves dividing the total market capitalization of 30 companies in the Index by a number called the Index Divisor. The Divisor is the only link to the original base period value of the SENSEX. It keeps the Index comparable over time and is the adjustment point for all Index maintenance adjustments. During market hours, prices of the index scrips, at which latest trades are executed, are used by the trading system to calculate SENSEX every 15 seconds and disseminated in real time.

How is the closing Index calculated? The closing SENSEX is computed taking the weighted average of all the trades on SENSEX constituents in the last 15 minutes of trading session. If a SENSEX constituent has not traded in the last 15 minutes, the last traded price is taken for computation of the Index closure. If a SENSEX constituent has not traded at all in a day, then its last day's closing price is taken for computation of Index closure. The use of Index Closure Algorithm prevents any intentional manipulation of the closing index value.

Answer 2

Its simple.
BSE Sensex is based on a 30 share index.
Every share has a particular weight or %.
index is built based on the mkt. capitalisation, i.e. the traded volume and the prices traded in the day.

please read the following literature


The Index was initially calculated based on the "Full Market Capitalization" methodology but was shifted to the free-float methodology with effect from September 1, 2003. The "Free-float Market Capitalization" methodology of index construction is regarded as an industry best practice globally. All major index providers like MSCI, FTSE, STOXX, S&P and Dow Jones use the Free-float methodology.

Free-float Methodology refers to an index construction methodology that takes into consideration only the free-float market capitalization of a company for the purpose of index calculation and assigning weight to stocks in Index. Free-float market capitalization is defined as that proportion of total shares issued by the company that are readily available for trading in the market. It generally excludes promoters' holding, government holding, strategic holding and other locked-in shares that will not come to the market for trading in the normal course. In other words, the market capitalization of each company in a Free-float index is reduced to the extent of its readily available shares in the market.

Free-float Methodology makes the index more broad-based by reducing the concentration of top few companies in Index. For example, the concentration of top five companies in SENSEX has fallen under the free-float scenario thereby making the SENSEX more diversified and broad-based.

Answer 3

sensex is usual image of inventory expenses of substantial companies .... if sensex is going down the inventory of majority of shares will pass down and if is going up it ability inventory of lots of the comp have long gone up.the Sensex is calculated making an allowance for inventory expenses of 30 distinctive BSE indexed companies. this is calculated utilising the “unfastened-glide industry capitalization” approach.

Answer 4

there are few rules to calculate it which is done by authorities... its done on the demand of the particular shares that public buys or sells...