NEW YORK (

TheStreet

) -- A nearly 30% decline so far this year has gotten

RadioShack

(RSH)

kicked out of the

S&P 500

.

Standard & Poor's said in a

press release

late Thursday that

Marathon Petroleum

, a proposed spin-off of

Marathon Oil

(MRO) - Get Marathon Oil Corporation (MRO) Report

. Marathon Oil will remain in the S&P 500 after the spin-off.

RadioShack, whose $1.4 billion market capitalization is "more representative of the mid cap market space" according to S&P, will join the S&P Midcap 400, replacing

Harte-Hanks

(HHS) - Get Harte-Hanks, Inc. Report

, which will move to the S&P Smallcap 600.

Harte-Hanks is pushing out

Hutchinson Technology

(HTCH)

, which S&P said has the smallest market cap in the index.

Shares of RadioShack closed Thursday at $13.20, up 2%, on volume of 4.5 million, above the issue's trailing three-month daily average churn of 3.4 million. The stock is down 30% year-to-date, and 40% in the past year. Its 52-week low of $12.28 came on June 16.

Other changes include

AMC Networks

TheStreet Recommends

( AMCXV) replacing

Boyd Gaming

(BYD) - Get Boyd Gaming Corporation Report

in the S&P Midcap 400; Boyd Gaming moving to the S&P Smallcap 600 to replace

StarTek

(SRT) - Get StarTek, Inc. Report

. AMC Networks is being spun off from

Cablevision Systems

(CVC)

, which will remain in the S&P 500.

Also,

Holly Corp.

( HOC) is replacing

Frontier Oil

( FTO) in the S&P Midcap 400, as Holly is in the process of acquiring Frontier Oil.

Entropic Communications

(ENTR) - Get ERShares Entrepreneur 30 ETF Report

is replacing Holly Corp. in the S&P Smallcap 600.

All these index changes are expected to take place after the market close on June 30.

--

Written by Michael Baron in New York.

>To contact the writer of this article, click here:

Michael Baron

.

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