Social mobility or rather Income mobility describes the ability of an individual to move up in the income strata of the society. This is also an indicator of the income elasticity.  As seen in the figure a larger number for this metric shows a smaller chance of being able to move up the income groups based on previous wealth. Surprisingly, there is a higher income inequality in the US and also a lesser chance of changing income strata despite being a developed country.

Social mobility versus income comparison

Get 10 new $100 bills. Cut them into thirds. Put all of the left sides in one envelope, right sides in another, and middles in a third. Send the envelopes separately.

1/3rd of a bill is not legal tender. Therefore, each shipment has no value. However, banks can reissue the money as long as you have > 51% of the material for each bill. Therefore, if one of the shipments is lost, the recipient still gets $1,000. [1]

You can fully eliminate the risk of loss (and reduce shipping costs) at the expense of latency. Wait for the recipient to acknowledge the receipt of each shipment before sending the next one. If a shipment is lost, split the bills into smaller parts so that you always ensure that you and the recipient have more than 51% of the bills. Once the recipient has 51% of the bills, you can stop making shipments, saving you costs.