Changes for Version 2.0 CHAMP Density:
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1. Interpolation of satellite attitude data improved
	a. methods updated to handle missing data
	b. index (NumInterp variable) added to data set indicating any interpolation of attitude data
2. Accelerometer instrument X-axis biases reprocessed and smoothed
3. Coefficient of drag updated from method of Cook [1965] to Sentman [1961]
	a. includes more realistic formulation of the coefficient of drag
	b. includes the effect of 'thermal drag', a phenomenon that increases the coefficient of drag for long satellites
4. Variable 'LatBin' added and 'Lat' modified
	a. LatBin gives the center of the current averaging bin
	b. Lat gives the mean position of the satellite at data points within the current averaging bin
	c. This ensures that the satellite position (defined by variables Lat, Lon, and Height) is consistent
5. Reference frame used to compute wind was changed
	a. In the formula  Wy = Vy - Vx*Ay/Ax, the subscript 'x' refers to the direction of the satellite velocity with respect to the atmosphere (assumed to be co-rotating with the earth)
	b. The 'y' subscript refers to the direction normal to x and the nadir direction
	c. The direction of the 'y' axis is given in the East/North frame
6. Accelerometer instrument Y-axis bias factors are computed by assuming that over a 3-day period, the mean of the low-latitude winds (< +-30 deg) is equal to zero