TA-100 Index

The TA-100 Index, typically referred to as the Tel Aviv 100, is a of the 100 most highly capitalised companies listed on the (TASE). The index began on 1 January 1992 with a base level of 100. The highest value reached to date is 1247.92, in January 2011.

The index is maintained by the and is calculated in real-time during trading hours and published every 30 seconds. The index combines the companies that are listed in the TA-25 and TA-75 indices.

The TA-25 Index is the TASE's flagship index. It was first published in 1992 under the name "MA'OF Index". The TA-25 index tracks the prices of the shares of the 25 companies with the highest market capitalization on the exchange. It serves as an underlying asset for options and futures, Index-Linked Certificates and Reverse Certificates traded on the exchange and worldwide. The index also began on 1 January 1992 with a base level of 100.

The TA-75 is a share index of the 75 most highly capitalised companies listed on the , which are not included in the TA-25 index. The index began in 1999 with a base level of 100.

Since February 2008, the TA-100 is calculated using a free float method, the total market capitalization of the companies weighted by their effect on the index, so the larger stocks would make more of a difference to the index as compared to a smaller market cap company. The basic formula for any index is (be it capitalization weighted or any other stock index).

The Free float Adjustment factor represents the proportion of shares that is floated as a percentage of issued shares. The free-float method, therefore, does not include restricted stocks, such as those held by company insiders.

A company’s weight in the index has an upper-limit of 9.8%, the weight of a company that should be higher is limited to 9.8% and the rest is divided between the other constituents of the index. Since October 2007 this restriction has set the effective weight of Teva Pharmaceutical Industries at 9.8%.

To be included in the TA-25 index the company’s stock also need to adhere to the following requirement: Meet a public holding threshold of at least 25% and a minimal value of 600 million NIS (to ensure that there is a significant Free float holding, which is not controlled by insiders).

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