Most commonly, patients describe acute tenderness in the buttock and sciatica-like pain down the back of the thigh, calf and foot. Typical piriformis syndrome symptoms may include: 1  A dull ache in the buttock. 2  Pain down the back of the thigh, calf and foot (sciatica). 3  Pain when walking up stairs or inclines.
There are currently 10 sectors and 68 industries. Three of the 68 industries do not have companies represented in the S&P 500 Index; therefore, performance is not available for Marine, Transportation and Infrastructure, and Water Utilities.
There are four primary types of economic systems in the world: traditional, command, market and mixed. Each economy has its strengths and weaknesses, its sub-economies and tendencies, and, of course, a troubled history.