This joint report from the CIA and the Society of Actuaries illustrates the impacts of numerous variables on post-level term lapse rates.
The report finds that the shock lapse rate tends to be highest when premiums move from one level to the next, and it is higher for older issue ages and for annual rather than monthly premium modes. Similarly, mortality deterioration appears to increase by issue age and by the size of premium jump.
Pricing and valuation actuaries will find this report useful in building assumptions.