function erfcxY100( y100 ) {
	var t = floor( y100 );
	var f = table[ t ];
	return f( 2*y100 - ((2*t) + 1) );
}
Given `y100 = 100*y`, where `y = 4/(4+x)` for `x >= 0`, compute `erfc(x)`.

## Notes

-   Uses a look-up table of 100 different Chebyshev polynomials or y intervals \[0,0.01\], \[0.01,0.02\], ..., \[0.99,1\], generated with the help of Maple and a little shell script.
-   This allows the Chebyshev polynomials to be of significantly lower degree (about 1/4) compared to fitting the whole \[0,1\] interval with a single polynomial.

@private
@param {number} y100 - scaled argument
@returns {number} complementary error function