Web companies from China, Russia and elsewhere are also rushing to list on American exchanges. Shortly after LinkedIn’s stunning debut, which saw its share price more than double, Yandex, Russia’s largest search engine, floated its shares on the NYSE.　　

LinkedIn, a social network for professionals, kicked things off last month with a flotation on the New York Stock Exchange (NYSE) that valued it at $8.8 billion—572 times its profits last year—at the end of the first day of trading.

請問第一段的which 指代什么呢？第二段的that 指的是什么呢？勞煩老師作答。

Web companies from China, Russia and elsewhere are also rushing to list on American exchanges. Shortly after LinkedIn’s stunning debut, which saw its share price more than double, Yandex, Russia’s largest search engine, floated its shares on the NYSE.　　　　

句中的 which 指 debut。　　

LinkedIn, a social network for professionals, kicked things off last month with a flotation on the New York Stock Exchange (NYSE) that valued it at $8.8 billion—572 times its profits last year—at the end of the first day of trading.　　

這個句子有點奇怪，提出個人看法，向大家請教。　　

句中的that好像是指代the New York Stock Exchange (NYSE)，但意義上顯然有問題，因為the New York Stock Exchange (NYSE)是一個專有名詞，其中的that又是引導一個限制性定語從句，這樣的話，其意可能就是：對它估值88億美元的紐交所。那言外之意，是不是還有其他的紐交所。　　

我的理解是，that valued it at $8.8 billion 似乎應改為一個非限制性定語從句，即which valued it at $8.8 billion（并在 which 前使用逗號）。這樣一來，非限制性定語從句 which valued it at $8.8 billion 就成了一個補充信息，無論語法和意義都通順了。　　

但是，我在 google 上查了一下，這個句子好像是出自英美人之手，按理不會出現這樣的語法錯誤。所以我就想，是原作者的筆誤？還是另有解釋？請朋友們指教，謝謝！