Is Martin Midstream Partners LP overvalued or undervalued?

As of 13 February 2019, the valuation grade for Martin Midstream Partners LP has moved from very attractive to risky, indicating a significant shift in its investment appeal. The company appears to be overvalued, especially given its negative price-to-book value of -1.66 and a high EV to EBITDA ratio of 5.77. Additionally, the EV to Sales ratio stands at 0.82, suggesting that the market may not be valuing its sales effectively compared to peers.
In comparison to its peer NGL Energy Partners LP, which has a P/E ratio of 15.66 and an EV to EBITDA of 5.90, Martin Midstream's metrics highlight its relative weakness. The company's recent stock performance has been poor, with a year-to-date return of -14.48% compared to the S&P 500's positive return of 12.22%, reinforcing the notion that it is currently overvalued.