The Dow Jones Industrial Average (DJI - 12,718.70) is down 178 points, or 1.4%, after the Labor Department reported that non-farm payrolls rose by just 80,000 in June -- falling short of Wall Street's projections. Elsewhere, the CBOE Market Volatility Index (VIX - 17.97) is up 0.5 point, or 2.7%.

Here are a few noteworthy stats at midday:

1. The equity put/call volume ratio across all 10 options exchanges stands at 1.01, with 2.5 million puts changing hands so far today, versus 2.4 million calls.
   
   
2. Among the equities with put-skewed activity is building materials manufacturer USG Corporation (NYSE:USG - 20.28), which has declined about 2.5% so far today. Currently, puts make up 76.1% of the security's intraday option volume.
   
   
3. The put/call volume ratio on the iPath S&P 500 VIX Short-Term Futures ETN (VXX) sits at 1.27, with puts comfortably outnumbering calls.
   
   
4. The Nasdaq shows an advance/decline ratio of 0.31, indicating that the number of downward movers more than triples the advancers.
   
   
5. Among the Nasdaq's major decliners is Acme Packet, Inc. (NASDAQ:APKT - 15.86), which has shed about 13.8% in intraday action -- and tagged a new multi-year low of $15.53. The software concern was slapped with a price-target cut to $13 from $20 at Mizuho Securities this morning after APKT offered a weak second-quarter outlook based on disappointing preliminary earnings results.