You won't get a satisfactory answer to this question. I'll try to elaborate why. But, please, be prepared for the fact that you really won't like the answer.

The whole concept of past vs present contributions is a misnomer unless the pension fund is no longer accepting contributions at all.

The 1st reason for it is that in order to offset inflation, the money has to be invested. The rate of return of an investment is usually proportional to the level of its risk. Risks are offset by various insurance instruments. But these insurance instruments also cost money.

Generally any open fund (a fund which continues to receive contributions) has a plan for future payments and future liabilities. In this sense, the future payments to pensioners server the same as the future payments on these insurance instruments. Both are future liabilities.

The cost of the payments to pensioners is fairly well-known (based on certain assumptions about life expectancy). The cost of derivatives (these are really the insurance instruments) is not known because they are determined by future market conditions. The amount of money that will continue to be contributed to the plan is not well-known because it is effected by the workers ability and willingness to contribute (it does happen from time to time that workers' representatives do not make payments because the times "are tough"). The amount that the investments return is also volatile.

There is a whole area of expertise called "financial risk management" which seeks to determine relationships between various possible future events and how these events would change the holdings of the pensions plans. Its aim to make sure that the risks taken by the pension plans make it highly unlikely that the liabilities will reduce the plans' future ability to pay.

This may have been too long an answer. But if you read through all of it, then here's why the question doesn't make sense. The payments made into the plan are no different than payments made by investments made by the plan. They are determined by multiple factors. The sum total of the payments received by the plan (both from the investments and from the payments made by workers) should not be lower than the liabilities. If it is, then the plan is losing money.

However, the payments are made to the plan on nearly continued basis. And the payments are paid out by the plan on regular basis. So the distinction between past money and "current" money is moot. The only distinction which can be made is whether the plan's assets are increasing or decreasing.

Oh, and it doesn't matter if the money is collected by an employer or the government (in the form of taxes). The mechanism remains the same. There are current payments into the plan and payouts by the plan.

You won't get a satisfactory answer to this question. I'll try to elaborate why. But, please, be prepared for the fact that you really won't like the answer.

The whole concept of past vs present contributions is a misnomer unless the pension fund is no longer accepting contributions at all.

The 1st reason for it is that in order to offset inflation, the money has to be invested. The rate of return of an investment is usually proportional to the level of its risk. Risks are offset by various insurance instruments. But these insurance instruments also cost money.

Generally any open fund (a fund which continues to receive contributions) has a plan for future payments and future liabilities. In this consideration, the future payments to pensioners serve the same function as the future payments on these insurance instruments. Both are future liabilities.

The cost of the payments to pensioners is fairly well-known (based on certain assumptions about life expectancy). The cost of derivatives (these are really the insurance instruments) is not known because they are determined by future market conditions. The amount of money that will continue to be contributed to the plan is not well-known because it is effected by the workers ability and willingness to contribute (it does happen from time to time that workers' representatives do not make payments because the times "are tough"). The amount that the investments return is also volatile.

There is a whole area of expertise called "financial risk management" which seeks to determine relationships between various possible future events and how these events would change the holdings of the pensions plans. Its aim is to make sure that the risks, taken by the pension plans, make it highly unlikely that the liabilities will reduce the plans' future ability to pay.

This may have been too long an answer. But if you read through all of it, then here's why the question doesn't make sense. The payments made into the plan are no different than payments made by investments made by the plan. They are determined by multiple factors. The sum total of the payments received by the plan (both from the investments and from the payments made by workers) should not be lower than the liabilities. If it is, then the plan is losing money.

However, the payments are made to the plan on nearly continued basis. And the payments are paid out by the plan on regular basis. So the distinction between past money and "current" money is moot. The only distinction which can be made is whether the plan's assets are increasing or decreasing.

Oh, and it doesn't matter if the money is collected by an employer or the government (in the form of taxes). The mechanism remains the same. There are current payments into the plan and payouts by the plan.