I believe you need to add declaration of outputValue and use data type 'float' for this to work
outputValue = map (sensorValue, 0, 1023, 0, 5.00) // this line is probably wrong but am trying to work it out, I would like the reading to be from 0 to 5 with 2 decimal places on the display
and maybe something more like:
outputValue = 0.00488 * outputValue; // convert analog reading into Volts, 1 bit of analogRead = 4.88mV
or
outputValue = (1/1023)*outputValue;