What does the Marshall-Lerner condition look like if the country whose real exchange rate changes does not start out with a current account of zero? (The Marshall-Lerner condition is derived in...

What does the Marshall-Lerner condition look like if the country whose real exchange rate changes does not start out with a current account of zero? (The Marshall-Lerner condition is derived in Appendix 2 under the “standard” assumption of an initially balanced current account.)