Morphine was the first single-substance drug to be derived from a plant, in this case from the resin of the opium poppy (Papaver somniferum) by a German pharmacist named Setru â¦ rner, in 1803-1805. It was first sold commercially by Heinrich Merck in the 1820's.
1 To find percentiles outside of this range, use the PERCENTILE.INC function. The syntax on this function is exactly the same as for the PERCENTILE.EXC function.  If you will need this worksheet to run on versions of Excel prior to 2007, use PERCENTILE instead of PERCENTILE.EXC or PERCENTILE.INC.
Percentile - The weighted percentile method. 1  In addition to the percentile function, there is also a weighted percentile, where the percentage in the total weight is counted instead of the total number. There is no standard function for a weighted percentile.