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.
Primary, secondary, tertiary and quaternary industryIndustry can be classified using a four-way division. Over time, the percentage of the population of a country working in these different sectors of industry will change as the country develops. This is covered in the 'Employment structures' section.-