Apple Inc.’s inclusion in the Dow Jones Industrial Average means every other component will have a little less influence on the Dow’s price.

The Dow is a price-weighted index, which means the price is determined by the price changes of its components, rather than percentage changes. Because Apple’s stock AAPL, -3.17% is nearly four times the price of AT&T’s stock T, -0.48% , which it replaced, the divisor used to calculate the index has declined slightly, in an effort to make the change seamless to the outside observer.

The new divisor out to six digits is 0.149859, according to S&P Dow Jones Indices, which owns the Dow indexes. That means every $1 move in any component’s stock will move the Dow by about 6.67 points. S&P Dow Jones Indices is a unit of McGraw Hill Financial US:MHFI.

The previous divisor of 0.155716 meant that each $1 move was worth a 6.42-point change move in the Dow.

A 1% move in Apple’s stock--about $1.28 at Wednesday’s closing price--would move the Dow by about 8.54 points. That is nearly five-times the influence of a 1% move in General Electric’s stock GE, -2.41% , which equates to about 26 cents. General Electric is currently the lowest-priced Dow component, while Apple’s is the fifth-highest priced Dow component, behind Goldman Sachs Group GS, +0.01% , 3M Co. MMM, -1.64% , IBM Corp. IBM, -1.72% and Boeing Co. BA, -3.81%

In contrast, the S&P 500 is a market-capitalization weighted index. Since Apple has a $748.3 billion market cap, its stock has more than twice the influence on the S&P as that of Exxon Mobil Corp. XOM, -1.61% , which is the second-most heavily-weighted component with a $361 billion market cap.

Apple’s stock was little changed in morning trade Thursday. It was recently down 11 cents, or 0.1%, meaning it was shaving off less than a point from the Dow, after being up as much as 78 cents earlier in the session.

Visa Inc.’s stock V, -1.29% also affected the Dow’s divisor on Thursday, as the four-for-one stock split announced in late January went into effect.

Read more about what Apple’s addition to the Dow will do to its stock.