Six out of 10 sectors advanced, as two of three major indexes ended higher in the stock market today. The S&P 500 Index's (^GSPC -0.46%) gains were even enough to send it to all-time closing highs, though the bullishness didn't translate to shares of Coach, (TPR -1.60%), Juniper Networks, (JNPR -1.16%), and ConAgra Foods, (CAG -0.95%), which ended as the three worst stocks in the benchmark index on Thursday. The S&P 500, for its part, added two points, or 0.1%, to end at 1,959.

Two of today's three worst stocks are actually repeat offenders, having finished at the bottom of the market yesterday, as well. Coach is one of those unfortunate names, plunging 8.9% just after sliding 4% on Wednesday. Shares of the luxury retailer slumped yesterday after Barclay's lowered its price target on the stock. Today's more severe decline came after Coach itself all but confirmed fears that its sales will be in free-fall mode for some time. The company is closing a mind-boggling 70 stores in the next 12 months as the intensely competitive luxury-retail landscape forces Coach to retreat.

Shares of network equipment maker Juniper Networks shed 4.1% on Thursday after a notable analyst downgrade sent shares sliding. Mizuho analyst Matthew Hoffman downgraded shares to neutral from outperform, citing channel checks that indicated several major telecoms are ratcheting down their capex budgets. The telecommunications sector represents a massive end market for Juniper, and with AT&T and Sprint allegedly scaling back on spending, you can't blame investors for today's sell-off.

Slim Jim is one of ConAgra's many branded products. Source: Slimjim.com.

ConAgra Foods fell 3.6% on Thursday, piggybacking on yesterday's 7.3% losses. The $12 billion packaged foods giant is feeling the heat from a sudden and quite rapid shift in consumer sentiment: private-label brands are quickly losing the popularity once seen in the years immediately following the financial crisis. Once peaking at a 29% market share, private-label brand consumption now accounts for less than 20% of sales. ConAgra told investors yesterday that this contraction would have a notably negative impact on the company's fourth-quarter results, slated to be reported a week from today.