NEW YORK ( TheStreet) -- The following stocks were upgraded last week by TheStreet Ratings: Vanguard Natural Resources ( WNV), Pengrowth Energy ( PGH), Lincoln National ( LNC), Endurance Specialty Holdings ( ENH), Covance ( CVD), Brookdale Senior Living ( BKD - Get Report) General Growth Partners ( GGP), Foster Wheeler ( FWLT), PartnerRe ( PRE), Talisman Energy ( TLM), Forest Oil ( FST), Icahn Enterprises ( IEP - Get Report), LyondellBasell Industries ( LYB - Get Report) and Teekay ( TK - Get Report).

Vanguard Natural Resources was upgraded to buy from hold at TheStreet Ratings on Wednesday.

TheStreet Ratings gives Vanguard Natural Resources a B grade. The stock closed Friday at $27.52 and has ticked down 11 cents, or 0.4% year to date.

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Pengrowth Energy was upgraded to buy from hold at TheStreet Ratings on Wednesday.

TheStreet Ratings gives Pengrowth Energy a B- grade. The stock closed Friday at $8.66 and has fallen 17.76% year to date.


Lincoln National was upgraded to buy from hold at TheStreet Ratings on Wednesday.

TheStreet Ratings gives Lincoln National a B grade. The stock closed Friday at $23.11 and has risen 19% year to date.

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Endurance Specialty Holdings was upgraded to buy from hold at TheStreet Ratings on Wednesday.

TheStreet Ratings gives Endurance Specialty Holdings a B+ grade. The stock closed Friday at $41.16 and has risen 7.61% year to date.


Covance was upgraded to buy from hold at TheStreet Ratings on Wednesday.

TheStreet Ratings gives Covance a B- grade. The stock closed Friday at $46.56 and has risen 1.84% year to date.

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Brookdale Senior Living was upgraded to hold from sell at TheStreet Ratings on Wednesday.

TheStreet Ratings gives Brookdale Senior Living a C- grade. The stock closed Friday at $18.38 and has risen 5.69% year to date.


General Growth Partners was upgraded to hold from sell at TheStreet Ratings on Tuesday.

TheStreet Ratings gives General Growth Partners a C grade. The stock closed Friday at $17.90 and has risen 19.17% year to date.

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Foster Wheeler was upgraded to hold from buy at TheStreet Ratings on Tuesday.

TheStreet Ratings gives Foster Wheeler a B- grade. The stock closed Friday at $22.13 and has risen 15.62% year to date.


PartnerRe was upgraded to buy from hold at TheStreet Ratings on Tuesday.

TheStreet Ratings gives PartnerRe an A- grade. The stock closed Friday at $72.81 and has risen 13.39% year to date.

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Talisman Energy was upgraded to buy from hold at TheStreet Ratings on Tuesday.

TheStreet Ratings gives Talisman Energy a B- grade. The stock closed Friday at $11.60 and has fallen 9.02% year to date.


Forest Oil was upgraded to hold from sell at TheStreet Ratings last Monday.

TheStreet Ratings gives Forest Oil a C grade. The stock closed Friday at $10.93 and has fallen 19.34% year to date.

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Icahn Enterprises was upgraded to buy from hold at TheStreet Ratings last Monday.

TheStreet Ratings gives Icahn Enterprises a B- grade. The stock closed Friday at $44.38 and has fallen 10.22% year to date.


LyondellBassell Industries was upgraded to buy from hold at TheStreet Ratings last Monday.

TheStreet Ratings gives LyondellBassell Industries a B- grade. The stock closed Friday at $39.48 and has risen 21.51% year to date.

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Teekay was upgraded to buy from hold at TheStreet Ratings last Monday.

TheStreet Ratings gives Teekay a B- grade. The stock closed Friday at $41.15 and has risen 24.06% year to date.

-- Written by Alexandra Zendrian

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