This painting has appreciated in value by 100% over the past five years.

appreciated 是动词 appreciate 的过去分词形式。appreciate 由前缀 ap-（表示"朝向"）和词根 preci（价值）组成，本义是"认识到价值"，引申为"升值、增值"。在这里表示"（价值）上涨"的意思。