Supreme Court in Ghaziabad Development Authority v. Balbir Singh, (2004) 5 SCC 65, has observed that there is no fixed formula for fixing damages in the following manner-
8. However, the power and duty to award compensation does not mean that irrespective of facts of the case compensation can be awarded in all matters at a uniform rate of 18% per annum. As seen above, what is being awarded is compensation i.e. a recompense for the loss or injury. It therefore necessarily has to be based on a finding of loss or injury and has to correlate with the amount of loss or injury. Thus, the Forum or the Commission must determine that there has been deficiency in service and/or misfeasance in public office which has resulted in loss or injury. No hard-and-fast rule can be laid down, however, a few examples would be where an allotment is made, price is received/paid but possession is not given within the period set out in the brochure. The Commission/Forum would then need to determine the loss. Loss could be determined on basis of loss of rent which could have been earned if possession was given and the premises let out or if the consumer has had to stay in rented premises then on basis of rent actually paid by him. Along with recompensing the loss the Commission/Forum may also compensate for harassment/injury, both mental and physical. Similarly, compensation can be given if after allotment is made there has been cancellation of scheme without any justifiable cause.
9. That compensation cannot be uniform and can best be illustrated by considering cases where possession is being directed to be delivered and cases where only monies are directed to be returned. In cases where possession is being directed to be delivered the compensation for harassment will necessarily have to be less because in a way that party is being compensated by increase in the value of the property he is getting. But in cases where monies are being simply returned then the party is suffering a loss inasmuch as he had deposited the money in the hope of getting a flat/plot. He is being deprived of that flat/plot. He has been deprived of the benefit of escalation of the price of that flat/plot. Therefore, the compensation in such cases would necessarily have to be higher. … We clarify that the above are mere examples. They are not exhaustive. The above shows that compensation cannot be the same in all cases irrespective of the type of loss or injury suffered by the consumer.”