HSBC analyst Lilyanna Yang upgraded Ecopetrol (EC) to Buy from Hold with a price target of $20.50, down from $21. The analyst estimates the company's $1.5B joint venture with shale operator Occidental Petroleum (OXY) announced in August to be accretive on a standalone basis and better than initially thought at the time of the announcement. The asset should provide self-funded reserve upside to beyond 160M BOE of proven reserves, Yang tells investors in a research note. Further, the analyst believes the joint venture should help Ecopetrol better understand and de-risk gross resources in Colombia unconventionals.