今日早盘，"A系列"指数低开后持续反弹。截至午间收盘，中证A500指数、中证A100指数均上涨0.1%，中证A50指数上涨0.02%，相关ETF交投活跃， A500ETF易方达（159361）半日成交额近50亿元，获约2.5亿份净申购。 Wind数据显示，截至12月29日，A500ETF易方达（159361）今年以来年化跟踪误差仅0.34%，相对指数超额收益为2.85%，在规模百亿以上的同类产品 中位居第一。 每日经济新闻 【免责声明】本文仅代表作者本人观点，与和讯网无关。和讯网站对文中陈述、观点判断保持中立，不对所包含内容的准确性、可靠性或完整性提供任何明示或暗示的保证。请 读者仅作参考，并请自行承担全部责任。邮箱：news_center@staff.hexun.com （责任编辑：董萍萍 ） ...

Group 1 - The article discusses the importance of diversifying investments across different asset classes, including both RMB and foreign currency assets, as well as stocks and bonds [2] - It highlights the significance of USD bond funds as a crucial component of investment diversification [2] - A free course is offered to provide systematic knowledge on investing in USD bond funds, along with supplementary materials like course notes and mind maps for efficient learning [2] Group 2 - The article explains the concept of the CSI A500 index, which belongs to the A series of indices, and its classification into several major types [5] - It points out the drawbacks of market capitalization-weighted indices, such as increased index risk due to short-term speculative companies and high concentration in certain industries [5] - The A series indices incorporate two strategies: broad-based indices and strategy indices, along with industry and thematic indices to enhance long-term returns [6]