The gross margin of our wholesale business improved during the fourth quarter as a result of several factors including the $4.2 million of TCM sales as a result of cultivating our herbs and the previously mentioned group transfer of group sales from our retail pharmacies to our wholesale business. The margin for our harvested TCM sold during the fourth quarter of fiscal year 2012 was approximately 89% while group sales typically reflect the margins we have in our retail business.
Sales and Marketing Expenses. Our sales and marketing expenses increased by $3,659,495 or 75.6% from a year ago as a result of increased rent, labor amortization costs, and promotion activities for our online pharmacy and wholesale business. Sales and marketing expenses as a percentage of our revenue increased to 9.0%, from 6.9% a year ago. We expect that our sales and marketing expenses will increase as we continue to expand our store network, online pharmacy and wholesale business.
General and Administrative Expenses. Our general and administrative expenses increased by $3,858,446 or 81.7% from a year ago. General and administrative expenses as a percentage of our revenue increased to 9.1% from 6.8% for the year ended March 31, 2011. The increase in absolute dollars as well as a percentage of revenue related to professional fees incurred as a U.S. publicly traded company, increased salaries, and administration cost related to new business such as Jiuxin Medicine. As we continue to open drugstores, further develop our infrastructure, and incur expenses related to being a U.S. public company, we anticipate that our general and administrative expenses will increase in absolute dollars as well as a percentage of total revenues.
Income from Operations. As a result of increase in both sales and marketing expenses and general and administrative expenses, our income from operations decreased by $1,097,234 or 9.5% from a year ago. Our operating margin for the years ended March 31, 2012 and 2011 was 11.1% and 16.5%, respectively.Income Taxes. Our income tax expense decreased by $874,980 from a year ago, as a result of lower taxable income and an income-tax waiver granted to Qianhong Agriculture. Net Income. As a result of the foregoing, our net income decreased by $291,979 from a year ago. Conference Call Information The Company will host a conference call to discuss its fiscal year 2012 results on Tuesday, July 3, 2012, at 8 a.m. Eastern Time. To participate in the conference call, please dial 1-877-870-5176 from North America. International participants can access the call by dialing 1-858-384-5517. A live audio webcast of this conference call will be available under the Investor Relations section of the Company's website at http://www.chinajojodrugstores.com. A replay of the call will be available beginning the same day at approximately 11 a.m. Eastern Time by dialing 1-877-870-5176 or -1-858-384-5517 with pin #4550271. The replay will also be available on the company website. About China Jo-Jo Drugstores, Inc. China Jo-Jo Drugstores, Inc., through its subsidiaries and contractually controlled affiliates, is a retailer and wholesale distributor of pharmaceutical and other healthcare products in the People’s Republic of China. As of June 28, 2012, the Company has 64 retail pharmacies throughout Zhejiang Province and Shanghai.