Add 4.631m to data values 1973-1980 to refer to RLR<br>Add 4.668m to data values 1981-1987 to refer to RLR<br>Add 4.695m to data values for 1988 to refer to RLR<br>Add 4.701m to data values 1989-1993 to refer to RLR<br>Add 4.712m to data values 1994 onwards to refer to RLR<br>RLR is 8.600m below primary benchmark BM Kamaisi